Photosynthesis evolution

WEBVTT
Kind: captions
Language: en

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- [Instructor] In this
video, we are going to talk

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about the evolution of
photosynthesis on Earth

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because that's the only place that,

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at least so far, we're aware
of photosynthesis occurring.

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I personally believe that it's occurring

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in many places in the universe

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but we don't really know just yet.

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But first, a reminder of
what photosynthesis even is.

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It's the process where organisms

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are able to take carbon
dioxide in the atmosphere

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in the presence of water.

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And then use the sun's
energy, so sunlight,

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to then produce sugars,

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C6H12O6

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and three oxygen, so O2.

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Now, the way I've written it,

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this chemical equation right
over here, it hasn't balanced.

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So see, I have six carbons here,

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so let me put a six out front there.

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But now, let's see, I
have 12 hydrogens here.

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I only have two hydrogens here,

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so let me multiply this by six as well.

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And let's see, on the left-hand side,

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I have two oxygens times six is 12

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plus another six oxygens, 18 oxygens,

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so I need 18 oxygens over here.

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I already have six right over here,

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so I'll need another 12 right over here,

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so I'll put a six out front.

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So, I have balanced that.

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It's important for you to realize

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that this is a really big deal.

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You would not exist
without photosynthesis,

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and I know what you're thinking.

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You don't photosynthesize things.

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But the things that you eat

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or the things that you eat,
the things that they eat,

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they do some sort of photosynthesis.

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At the end of the day, our
energy is coming from the sun.

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Even if you're eating an animal,

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that animal might be eating another animal

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that eats a plant, and that
plant is using the sun's energy

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and it's storing it in the form

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of carbon-based molecules,
oftentimes sugars.

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And then when we eat these things,

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we are able to produce energy for them

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and do things like educational videos.

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But an interesting question
is where does this come from.

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And a straightforward answer

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is we don't have all the answers

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but scientists have a reasonably good idea

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of where it probably came from.

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Today, we can observe cyanobacteria.

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This is what cyanobacteria looks like.

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It is like all bacteria prokaryotic

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and it is able to conduct photosynthesis.

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And scientists believe

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that organisms not too
different from cyanobacteria,

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probably an ancestor of cyanobacteria,

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existed on Earth two
and half, three billion,

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maybe even older,

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maybe even further back
in time, years ago,

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and that's early in Earth's history.

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Earth has only been around

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for about four and a half billion years.

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And that ancestor of
cyanobacteria, like cyanobacteria,

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was able to take carbon
dioxide in the atmosphere

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in the presence of water
and produce oxygen.

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And even though this is bacteria

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and each of these
organisms are very small,

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in aggregate, they can have
a pretty significant impact.

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For example, this is a
cyanobacteria plume near Fiji

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and you can see that these
are pretty significant things

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that can be a significant contributor

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to oxygen in the atmosphere.

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And scientists believe

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that it was these
ancestors of cyanobacteria

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that as they evolved on Earth

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and started growing and
growing and multiplying

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that they started to
affect Earth's atmosphere.

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So, what you see in this
chart right over here

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is our best sense of
what the oxygen content

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in the atmosphere was
if we go back in time.

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And we can start to figure this out

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based by looking at rock
samples that are very, very old,

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by looking at the fossil
record, very, very old.

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So, just so you get, you
understand what's going on here,

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this horizontal axis right over here,

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this is billions of years ago.

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This is one billion years
ago, two billion years ago,

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three billion years ago,
3.8 billion years ago,

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so it covers most of Earth's history.

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If you just wanna put things in context,

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humans, modern humans
have only been around

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for about two or 300,000 years,

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so we wouldn't even show up as a pixel

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on this diagram right over here.

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So we're going back into deep time.

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And scientists believe

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that the first photosynthetic organisms

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might have evolved approaching
three billion years ago,

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although we're not exactly sure.

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And those organisms might
have been producing oxygen

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from the photosynthesis, but
it might have been absorbed

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by things like the ocean.

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But eventually, those organisms,

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probably these ancestors of cyanobacteria

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became significant enough

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that the oxygen started
pouring in the atmosphere,

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and we start to see that right over here.

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Before this point,

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the oxygen was pretty
close to zero percent

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and then right over here at
the Great Oxygenation Event,

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I'll just call it GOE,

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all of a sudden, oxygen becomes a larger

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and larger percentage of the atmosphere,

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and these two lines represent
two different estimates

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of what percentage of
the atmosphere oxygen was

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at these various times,

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and it grew all the way to modern times

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where oxygen is roughly 20
or 21% of our atmosphere.

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And the reason why

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this is sometimes called
the Oxygen Catastrophe,

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is that there were a lot
of anaerobic organisms

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that found oxygen poisonous,

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and so there was a great extinction event

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from all of these oxygen
in the atmosphere,

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but it was not a catastrophe
for what eventually would be us

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because we are dependent,
not just on the sugars

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from photosynthesis,
but we're also dependent

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on the oxygen from photosynthesis.

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We use this oxygen to conduct respiration.

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You can almost view respiration
as a backwards process.

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You take your sugars and
in the presence of oxygen,

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you are able to extract that
energy from those sugars

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so that we can live.

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Now, an interesting question
is at what point did we go

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from these prokaryotic bacteria organisms

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to eukaryotic organisms

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that are able to perform photosynthesis?

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Most notably, plants.

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Well, this goes back to
endosymbiosis theory.

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We have a whole other video on that,

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but it's this idea that the ancestors

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of the cyanobacteria might
have lived in symbiosis

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with another eukaryotic cell,

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where the cyanobacteria ancestor

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was able to harness light energy

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to produce sugars for the larger cell.

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And in return, the larger cell

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was able to give protection or nutrients.

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And so, we believe, based
on endosymbiosis theory

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that chloroplasts, and right
over here, you see plant cells

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with visible chloroplasts in them,

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that chloroplasts are actually descendants

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of those ancestors of cyanobacteria,

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cyanobacteria would be
other descendants of them,

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but these are the ones
that started to live

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in symbiosis with what would
later become plant cells.

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And good evidence that
these might have ancestors

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that used to live independently
is that they have DNA

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that is very similar to
the DNA of cyanobacteria.

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They have ribosomes, their own ribosomes,

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that are very similar to the
ribosomes of cyanobacteria.

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And so, like mitochondria,
we believe chloroplast

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originated as independent
bacteria-like organisms

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and eventually were engulfed
into eukaryotic cells.

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So, I will leave you there.

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Photosynthesis is a big deal,
and it's really interesting

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to think about where it came from.

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It likely evolved on Earth
many billions of years ago,

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probably close to three billion years ago,

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but around 2.3, 2.4 billions years ago,

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it fundamentally changed the planet

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where you had oxygen
pouring into the atmosphere,

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killing a lot of organisms,

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but making it possible for
many other organisms to live.

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And those early photosynthetic organisms,

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some of them had descendants

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that ended up living in symbiosis

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with larger eukaryotic cells

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that would eventually evolve
into things like plant cells.


Immigration and migration in the Gilded Age

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Kind: captions
Language: en

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- [Instructor] Here's a graph
showing the population growth

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in four US cities from 1860 to 1900.

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In 1860, before the Civil War,

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New York City was the biggest
city in the United States,

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but even it didn't have
more than a million people.

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There wasn't a single city
of more than a million

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in the whole country at that point.

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Compare that to just 40
years later when not one,

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but three cities had
passed the million mark,

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and New York had nearly
3.5 million residents.

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Proportionally, Chicago's
population growth

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was even more drastic,

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from only about 100,000 residents in 1860,

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it got 17 times bigger by 1900,

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with about 1.7 million residents.

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Traditionally,

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Americans had been a pretty
rural farming people,

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but starting in the late 19th century,

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there was a rapid shift
towards urbanization.

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By 1920, urban residents would
outnumber country dwellers

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in the United States for the first time.

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And today, more than 80% of
Americans live in cities.

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So what led to this explosion
in the population of cities

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in the decades after the Civil War?

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The major factors behind this shift

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were industrialization,
immigration, and migration.

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Now we've been talking
about those three things

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in various forms in American
history up until this point,

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from the cool inventions of
the first industrial revolution

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to the influx of Irish and
German immigrants in the 1840s

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to the movement of
Americans ever westward.

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So industrialization,
immigration, and migration

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weren't new forces in American society,

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but there were unique aspects of all three

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of these processes during the Gilded Age

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that contributed to the
development of cities in this era.

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One thing that changed was the nature

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of work that people did.

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During the Gilded Age,

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there was a tipping point in
the American labor market.

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In 1880, for the first time ever,

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the number of people who worked
for someone else for wages,

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people who had a boss and needed

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to do what they said to get paid,

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outnumbered Americans who
worked for themselves,

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like farmers who could
decide for themselves

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when to sow or harvest their crops.

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The second industrial revolution,

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which began after the Civil War,

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was a booming era of expansion
and industrial production.

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So there were a lot of
factory jobs available,

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and most of those jobs were
for unskilled laborers,

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that is workers who don't require any kind

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of special training
before they start a job.

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So there was an overall
transition from farm work that

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was self-directed to unskilled
factory work done for a boss.

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Another change during the Gilded Age

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was in who was doing the
immigrating and migrating.

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Until the 1840s,

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most immigrants to the United States

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had been Protestant Christians

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from northern and western Europe,

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and they were relatively
well off financially.

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After the Civil War, a
variety of factors abroad,

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combined with the wide availability

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of jobs in the United States,

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brought different types of
immigrants to American cities.

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These new immigrants, as they were called,

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tended to be from southern
and eastern Europe,

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Mexico, and Asia,

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and they differed from old
immigrants in that they tended

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to be poorer, have darker complexions,

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and practiced Catholicism or Judaism

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instead of Protestantism.

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In addition in this era,

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African Americans from the south began

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to migrate to northern
and mid-western cities.

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All of these immigrants and migrants

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created a large industrial workforce.

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But why did they all move to the city?

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Let's take a look at some
of the push and pull factors

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that prompted people to uproot themselves

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and head to American cities
during the Gilded Age.

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First, there were push
factors, or things that were

00:03:58.410 --> 00:04:02.160
pushing people out of their
previous living situations.

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A big one was poverty and just a lack

00:04:04.561 --> 00:04:07.730
of financial mobility at home.

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Farmers in many countries were
hit hard by the mechanization

00:04:10.414 --> 00:04:13.300
of agriculture, which
happened in this time period.

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About a third of the people
moving to cities were Americans

00:04:16.746 --> 00:04:20.930
leaving farms and heading to
the city for industrial jobs.

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Another push factor was persecution

00:04:23.410 --> 00:04:25.100
and discrimination at home.

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The Russian government

00:04:26.300 --> 00:04:29.870
took an increasingly intolerant
position towards Jews

00:04:29.870 --> 00:04:30.880
in this time period,

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who were subject to mob violence

00:04:32.810 --> 00:04:35.490
and campaigns of ethnic
cleansing in Europe.

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In the American south, the
emergence of Jim Crow laws

00:04:39.020 --> 00:04:42.120
and an increase in lynchings
were among the reasons

00:04:42.120 --> 00:04:45.530
that African Americans elected
to leave after the Civil War.

00:04:45.530 --> 00:04:49.380
But what were the pull factors
that landed them in cities?

00:04:49.380 --> 00:04:52.370
For one thing, many struggling
immigrants from abroad

00:04:52.370 --> 00:04:54.480
didn't have the money to go anywhere else.

00:04:54.480 --> 00:04:57.040
So after they arrived,
they just stayed put.

00:04:57.040 --> 00:04:59.180
But the main reason that
people moved to cities

00:04:59.180 --> 00:05:01.050
is because that's where the jobs were.

00:05:01.050 --> 00:05:04.010
With the development of steam
power and electrification,

00:05:04.010 --> 00:05:07.430
factories no longer had to
be located next to waterways.

00:05:07.430 --> 00:05:10.220
So cities developed as industrial hubs.

00:05:10.220 --> 00:05:12.910
Often cities would develop as the center

00:05:12.910 --> 00:05:17.250
for one specific industry,
like steel in Pittsburgh,

00:05:17.250 --> 00:05:20.840
meat packaging in Chicago,
or clothing in New York.

00:05:20.840 --> 00:05:24.520
People also found communities
of support in cities.

00:05:24.520 --> 00:05:27.710
Earlier immigrants might
send money and information

00:05:27.710 --> 00:05:29.610
to their families and friends back home,

00:05:29.610 --> 00:05:32.520
helping them to move and get established.

00:05:32.520 --> 00:05:35.770
This facilitated the development
of urban neighborhoods,

00:05:35.770 --> 00:05:37.459
where people from similar backgrounds

00:05:37.459 --> 00:05:40.166
spoke the same language,
ate the same food,

00:05:40.166 --> 00:05:42.570
and provided each other with assistance.

00:05:42.570 --> 00:05:43.702
In these ethnic enclaves,

00:05:43.702 --> 00:05:46.440
people could get newspapers and even go

00:05:46.440 --> 00:05:49.027
to see theater performances
in their native languages.

00:05:49.027 --> 00:05:51.540
So let's finish by taking a look

00:05:51.540 --> 00:05:53.821
at two narratives of immigrants

00:05:53.821 --> 00:05:57.030
arriving in American
cities in this time period.

00:05:57.030 --> 00:06:00.230
The first one is from
Lee Chew, who immigrated

00:06:00.230 --> 00:06:05.230
to San Francisco from China
at age 16 in the year 1880.

00:06:05.320 --> 00:06:06.153
He wrote,

00:06:06.153 --> 00:06:07.577
"When I got to San Francisco,

00:06:07.577 --> 00:06:10.042
"which was before the
passage of the Exclusion Act,

00:06:10.042 --> 00:06:12.327
"I was half starved, because I was afraid

00:06:12.327 --> 00:06:14.049
"to eat the provisions of the barbarians.

00:06:14.049 --> 00:06:16.537
"But a few days living
in the Chinese quarter

00:06:16.537 --> 00:06:17.747
"made me happy again.

00:06:17.747 --> 00:06:19.897
"A man got me work as a house servant

00:06:19.897 --> 00:06:21.317
"in an American family.

00:06:21.317 --> 00:06:23.077
"When I went to work for
that American family,

00:06:23.077 --> 00:06:24.927
"I could not speak a word of English,

00:06:24.927 --> 00:06:26.355
"and I didn't know
anything about housework.

00:06:26.355 --> 00:06:28.747
"I did not understand
what the lady said to me,

00:06:28.747 --> 00:06:32.427
"but she showed me how to
cook, wash, iron, sweep, dust,

00:06:32.427 --> 00:06:35.877
"make beds, wash dishes, clean
windows, paint and brass,

00:06:35.877 --> 00:06:38.127
"polish the knives and forks, et cetera.

00:06:38.127 --> 00:06:38.960
"In six months,

00:06:38.960 --> 00:06:41.097
"I had learned how to do the
work of our house quite well,

00:06:41.097 --> 00:06:43.337
"and I was getting $5 a week and board

00:06:43.337 --> 00:06:45.587
"and putting away about $4.25 a week.

00:06:45.587 --> 00:06:47.157
"I had also learned some English.

00:06:47.157 --> 00:06:49.457
"I sent money home to comfort my parents.

00:06:49.457 --> 00:06:52.307
"But though I dressed well and
lived well and had pleasure,

00:06:52.307 --> 00:06:53.968
"going quite often to the Chinese theater

00:06:53.968 --> 00:06:56.047
"and to dinner parties in Chinatown,

00:06:56.047 --> 00:06:59.120
"I saved $50 in the first six months."

00:06:59.120 --> 00:07:01.163
The second one is from Mary Antin,

00:07:01.163 --> 00:07:04.482
who immigrated to Boston
from what is now Belarus

00:07:04.482 --> 00:07:08.650
at the age of 13 in the year 1894.

00:07:08.650 --> 00:07:09.483
She wrote,

00:07:09.483 --> 00:07:13.087
"The first meal was an object
lesson of much variety.

00:07:13.087 --> 00:07:16.127
"My father produced several
kinds of food ready to eat,

00:07:16.127 --> 00:07:18.527
"without any cooking, from little tin cans

00:07:18.527 --> 00:07:20.177
"that had printing all over them.

00:07:20.177 --> 00:07:22.507
"He attempted to introduce us to a queer,

00:07:22.507 --> 00:07:25.347
"slippery kind of fruit,
which he called banana,

00:07:25.347 --> 00:07:27.367
"but had to give it up for the time being.

00:07:27.367 --> 00:07:30.037
"On our second day, a little
girl from across the alley

00:07:30.037 --> 00:07:32.327
"came and offered to conduct us to school.

00:07:32.327 --> 00:07:34.827
"My father was out, but we five between us

00:07:34.827 --> 00:07:36.987
"had a few words of English by this time.

00:07:36.987 --> 00:07:38.177
"We knew the word school.

00:07:38.177 --> 00:07:39.087
"We understood.

00:07:39.087 --> 00:07:41.647
"This child who had never
seen us 'til yesterday,

00:07:41.647 --> 00:07:43.337
"who could not pronounce our names,

00:07:43.337 --> 00:07:45.287
"who was not much better dressed than we,

00:07:45.287 --> 00:07:47.646
"was able to offer us the
freedom of the schools of Boston.

00:07:47.646 --> 00:07:50.697
"We had to visit the stores and be dressed

00:07:50.697 --> 00:07:53.517
"from head to foot in American clothing.

00:07:53.517 --> 00:07:56.047
"We had to learn the
mysteries of the iron stove,

00:07:56.047 --> 00:07:58.127
"the washboard, and the speaking tube,

00:07:58.127 --> 00:08:00.207
"and above all, we had to learn English.

00:08:00.207 --> 00:08:02.487
"With our despised immigrant clothing,

00:08:02.487 --> 00:08:05.957
"we shed also our impossible Hebrew names.

00:08:05.957 --> 00:08:07.107
"A committee of our friends,

00:08:07.107 --> 00:08:09.607
"several years ahead of
us in American experience,

00:08:09.607 --> 00:08:10.587
"put their heads together

00:08:10.587 --> 00:08:13.280
"and concocted American names for us all."

00:08:13.280 --> 00:08:16.380
So what similarities and
differences do you see

00:08:16.380 --> 00:08:20.110
between the experiences of
Lee Chew and Mary Antin?

00:08:20.110 --> 00:08:22.950
Why do you think they
immigrated to American cities,

00:08:22.950 --> 00:08:25.448
and what do you think
their lives would be like

00:08:25.448 --> 00:08:27.753
going forward in the Gilded Age?


Sectional conflict: Regional differences

WEBVTT
Kind: captions
Language: en

00:00:00.620 --> 00:00:01.840
- [Instructor] From the very beginning

00:00:01.840 --> 00:00:04.490
of English settlement in North America,

00:00:04.490 --> 00:00:06.560
the contrast between the Southern Colonies

00:00:06.560 --> 00:00:09.410
and the Northern Colonies was stark.

00:00:09.410 --> 00:00:11.720
Things didn't improve
much when the 13 Colonies

00:00:11.720 --> 00:00:15.610
rebelled in 1776 and became
an independent nation.

00:00:15.610 --> 00:00:17.590
Tensions over slavery flared

00:00:17.590 --> 00:00:20.210
during the crafting of
the U.S. Constitution,

00:00:20.210 --> 00:00:22.880
and repeatedly during the 19th Century,

00:00:22.880 --> 00:00:25.960
when compromises in 1820 and 1850

00:00:25.960 --> 00:00:28.370
barely maintained the fragile balance

00:00:28.370 --> 00:00:30.480
between Northern and Southern states.

00:00:30.480 --> 00:00:34.400
But in 1860, the wheels finally came off,

00:00:34.400 --> 00:00:36.040
and the Southern states seceded

00:00:36.040 --> 00:00:38.360
from the Union, starting the Civil War.

00:00:38.360 --> 00:00:41.520
After more than 80 years of compromise,

00:00:41.520 --> 00:00:44.810
why did the differences
between the North and the South

00:00:44.810 --> 00:00:48.710
finally become
irreconcilable in the 1850s?

00:00:48.710 --> 00:00:51.310
In other videos we've
traced the differences

00:00:51.310 --> 00:00:54.010
and similarities between
the North and South

00:00:54.010 --> 00:00:57.490
from the Colonial Era until the late 1840s

00:00:57.490 --> 00:01:00.610
in terms of economics, social structure,

00:01:00.610 --> 00:01:03.480
and commonly held ideas about slavery.

00:01:03.480 --> 00:01:06.710
Let's revisit those
comparisons for the years

00:01:06.710 --> 00:01:09.220
immediately leading up to the Civil War

00:01:09.220 --> 00:01:11.120
and see if we can identify why

00:01:11.120 --> 00:01:14.340
the conflict intensified in the 1850s.

00:01:14.340 --> 00:01:16.650
The difference between
the economies of the North

00:01:16.650 --> 00:01:19.300
and South began way back at the outset

00:01:19.300 --> 00:01:21.490
of colonization in North America

00:01:21.490 --> 00:01:24.390
when the cold climate
of the North prevented

00:01:24.390 --> 00:01:26.470
large scale plantation agriculture.

00:01:26.470 --> 00:01:28.530
Instead the Northern economy centered

00:01:28.530 --> 00:01:30.260
on trade and manufacturing.

00:01:30.260 --> 00:01:32.550
The first and second Industrial Revolution

00:01:32.550 --> 00:01:36.140
turned the Northern economy
into one based on factories,

00:01:36.140 --> 00:01:40.040
where men, women and children
worked for long hours,

00:01:40.040 --> 00:01:42.030
sometimes in dangerous conditions.

00:01:42.030 --> 00:01:45.410
In the 1840s the potato famine in Ireland

00:01:45.410 --> 00:01:48.740
and revolutions in Europe
prompted many Irish and German

00:01:48.740 --> 00:01:50.070
immigrants to come to Northern

00:01:50.070 --> 00:01:52.410
cities in search of factory jobs.

00:01:52.410 --> 00:01:54.300
But even though most factory workers

00:01:54.300 --> 00:01:56.230
in the North struggled to make ends meet,

00:01:56.230 --> 00:01:59.140
there was some opportunity
for social mobility,

00:01:59.140 --> 00:02:00.970
to climb the economic ladder.

00:02:00.970 --> 00:02:03.340
Therefore, the North also had a growing

00:02:03.340 --> 00:02:05.710
middle class in the mid-19th Century.

00:02:05.710 --> 00:02:07.810
Many in the lower class held out hope

00:02:07.810 --> 00:02:10.040
that they could move out West and start

00:02:10.040 --> 00:02:13.340
a small family farm in order
to become financially stable.

00:02:13.340 --> 00:02:15.970
So to recap, the class structure in the

00:02:15.970 --> 00:02:17.860
North looked kind of like this.

00:02:17.860 --> 00:02:22.130
A large working class of
laborers, many of them immigrants,

00:02:22.130 --> 00:02:25.870
a middle class of managers
and small business owners,

00:02:25.870 --> 00:02:28.470
and a small upper class of factory owners,

00:02:28.470 --> 00:02:30.760
bankers and successful merchants.

00:02:30.760 --> 00:02:33.660
In the South, cultivating
valuable cash crops

00:02:33.660 --> 00:02:36.660
to sell on the national
and international markets

00:02:36.660 --> 00:02:38.790
had always been the center of the economy.

00:02:38.790 --> 00:02:41.140
Cotton had slowly replaced tobacco

00:02:41.140 --> 00:02:43.380
as the number one crop in the South,

00:02:43.380 --> 00:02:45.430
and American cotton
plantations were producing

00:02:45.430 --> 00:02:49.510
nearly 70 percent of the
world's cotton supply by 1860.

00:02:49.510 --> 00:02:52.900
With agriculture working out
so well for plantation owners,

00:02:52.900 --> 00:02:56.170
there was no need to
industrialize as in the North.

00:02:56.170 --> 00:02:59.640
All the labor on plantations
was done by enslaved people,

00:02:59.640 --> 00:03:01.640
who had no hope of improving their lot

00:03:01.640 --> 00:03:03.570
in life except by running away.

00:03:03.570 --> 00:03:05.720
There was also a large number of poor

00:03:05.720 --> 00:03:08.570
white farmers who owned no slaves,

00:03:08.570 --> 00:03:11.360
and a few modest planters that owned

00:03:11.360 --> 00:03:13.850
fewer than 10 enslaved people.

00:03:13.850 --> 00:03:17.370
Despite the popular myth
of gigantic plantations

00:03:17.370 --> 00:03:20.990
across the South, only
one-tenth of a percent

00:03:20.990 --> 00:03:23.750
of slaveholders owned
more than 100 people.

00:03:23.750 --> 00:03:25.890
The class system in the South was

00:03:25.890 --> 00:03:28.750
extremely rigid and aristocratic,

00:03:28.750 --> 00:03:32.080
not far off from a
medieval feudal society,

00:03:32.080 --> 00:03:34.920
with a handful of wealthy white families

00:03:34.920 --> 00:03:36.960
dominating in each Southern sate.

00:03:36.960 --> 00:03:38.810
Wealth was measured in the South

00:03:38.810 --> 00:03:41.940
by the number of enslaved
people a planter owned.

00:03:41.940 --> 00:03:45.200
Poorer whites aspired
to buy enslaved people

00:03:45.200 --> 00:03:47.600
and become plantation owners themselves,

00:03:47.600 --> 00:03:49.070
but their prospects of doing so

00:03:49.070 --> 00:03:51.370
were pretty slim by the 1850s.

00:03:51.370 --> 00:03:53.900
Growing cotton quickly depleted the soil,

00:03:53.900 --> 00:03:56.340
and so both large plantation owners

00:03:56.340 --> 00:03:59.750
and whites who dreamed of
becoming large plantation owners

00:03:59.750 --> 00:04:02.550
looked to the West for
new lands to cultivate

00:04:02.550 --> 00:04:05.100
in order to expand the cotton kingdom.

00:04:05.100 --> 00:04:06.980
In short, the class structure in

00:04:06.980 --> 00:04:09.250
the South looked a little like this.

00:04:09.250 --> 00:04:13.180
A large permanent under
class of enslaved laborers,

00:04:13.180 --> 00:04:15.070
with non-slaveholding whites above

00:04:15.070 --> 00:04:17.940
them in rights and in economic power.

00:04:17.940 --> 00:04:20.070
Then there was a small number of planters

00:04:20.070 --> 00:04:22.300
who owned a few enslaved people.

00:04:22.300 --> 00:04:25.310
And at the very top was a tiny fraction

00:04:25.310 --> 00:04:29.000
of large planters who owned
more than 100 enslaved people.

00:04:29.000 --> 00:04:32.370
So how did these economic
differences lead to tension?

00:04:32.370 --> 00:04:34.420
Well first, there were
tensions over whether

00:04:34.420 --> 00:04:36.750
the economic policy of
the Federal Government

00:04:36.750 --> 00:04:39.620
promoted agriculture or manufacturing.

00:04:39.620 --> 00:04:43.100
Things like tariffs and the
expansion of the railroad

00:04:43.100 --> 00:04:45.500
turned into bitter fights
over whether the government

00:04:45.500 --> 00:04:48.970
was prioritizing the needs
of one section or the other.

00:04:48.970 --> 00:04:51.400
And then there was westward expansion.

00:04:51.400 --> 00:04:54.100
Both Northerners and
Southerners looked to the West

00:04:54.100 --> 00:04:56.310
for their future economic opportunities,

00:04:56.310 --> 00:04:58.310
and both sides suspected the other

00:04:58.310 --> 00:05:02.160
of trying to suppress their
paths to social mobility.

00:05:02.160 --> 00:05:04.340
The ideologies of the North and South

00:05:04.340 --> 00:05:07.890
also diverged sharply in the 1850s.

00:05:07.890 --> 00:05:10.830
In the North, most whites didn't object

00:05:10.830 --> 00:05:13.540
to slavery as it existed in the South,

00:05:13.540 --> 00:05:15.300
but worried about the potential

00:05:15.300 --> 00:05:17.240
expansion of slavery to the West.

00:05:17.240 --> 00:05:20.330
The Free Soil Movement aimed to preserve

00:05:20.330 --> 00:05:23.640
Western lands for small white farmers.

00:05:23.640 --> 00:05:26.210
There was also a growing
sense among Northerners

00:05:26.210 --> 00:05:29.740
that the South had too much
power in the Federal Government

00:05:29.740 --> 00:05:31.660
thanks to the Three-Fifths Compromise,

00:05:31.660 --> 00:05:33.760
which granted Southern
states representation

00:05:33.760 --> 00:05:37.240
in Congress for 60 percent
of its disenfranchised

00:05:37.240 --> 00:05:40.970
enslaved population in addition
to its white population.

00:05:40.970 --> 00:05:43.220
This was a fair charge to make.

00:05:43.220 --> 00:05:47.370
Many events of the 1850s
like the Fugitive Slave Act,

00:05:47.370 --> 00:05:49.190
which compelled Northern whites

00:05:49.190 --> 00:05:51.950
to assist in capturing runaway slaves,

00:05:51.950 --> 00:05:55.870
the Kansas-Nebraska Act,
which reopened the possibility

00:05:55.870 --> 00:05:59.440
of allowing slavery north of
the Missouri Compromise line,

00:05:59.440 --> 00:06:01.740
and the Supreme Court's
decision in the case

00:06:01.740 --> 00:06:03.560
Dred Scott versus Sandford,

00:06:03.560 --> 00:06:06.550
which claimed that
African-Americans weren't citizens,

00:06:06.550 --> 00:06:10.340
convinced Northerners that what
they called the slave power,

00:06:10.340 --> 00:06:12.460
had come to dominate government.

00:06:12.460 --> 00:06:15.080
Consequently, the abolition movement,

00:06:15.080 --> 00:06:19.050
which called for the immediate
end of slavery everywhere,

00:06:19.050 --> 00:06:22.950
grew considerably more
mainstream in the 1850s.

00:06:22.950 --> 00:06:25.320
Writers like Harriet Beecher Stowe,

00:06:25.320 --> 00:06:27.710
author of the influential abolitionist

00:06:27.710 --> 00:06:29.560
novel Uncle Tom's Cabin,

00:06:29.560 --> 00:06:32.010
activists like Frederick Douglas,

00:06:32.010 --> 00:06:34.340
who had escaped from slavery and toured

00:06:34.340 --> 00:06:36.750
the North lecturing about its evils,

00:06:36.750 --> 00:06:38.940
and vigilantes like John Brown,

00:06:38.940 --> 00:06:41.700
who led deadly raids on slaveholders,

00:06:41.700 --> 00:06:44.700
dramatized the moral evil of slavery

00:06:44.700 --> 00:06:47.940
to a growing audience in this time period.

00:06:47.940 --> 00:06:49.850
In contrast to the North,

00:06:49.850 --> 00:06:51.440
white Southerners believed they

00:06:51.440 --> 00:06:53.640
had the Constitution on their side,

00:06:53.640 --> 00:06:56.610
and that Northern attempts
to limit the expansion

00:06:56.610 --> 00:06:59.870
of slavery constituted an
assault on their liberty.

00:06:59.870 --> 00:07:04.210
In addition, white Southerners
began to craft a proactive

00:07:04.210 --> 00:07:07.700
defense of the institution
of slavery in the 1850s.

00:07:07.700 --> 00:07:11.510
Instead of treating slavery
like the South's embarrassing,

00:07:11.510 --> 00:07:16.190
but necessary, peculiar institution
as they had in the past,

00:07:16.190 --> 00:07:17.730
Southern commentators began to

00:07:17.730 --> 00:07:20.490
frame slavery as a positive good.

00:07:20.490 --> 00:07:21.850
They pointed to the conditions of

00:07:21.850 --> 00:07:23.730
immigrants in Northern factories,

00:07:23.730 --> 00:07:26.460
who might be injured
in an accident at work,

00:07:26.460 --> 00:07:29.590
and then be fired for no
longer being productive.

00:07:29.590 --> 00:07:31.430
Slave owners argued that they treated

00:07:31.430 --> 00:07:33.580
their enslaved laborers better than

00:07:33.580 --> 00:07:37.250
Northern factory owners
treated their wage slaves.

00:07:37.250 --> 00:07:41.160
Southern sociologist George
Fitzhugh wrote two books

00:07:41.160 --> 00:07:45.500
arguing that slavery was
preferable to the kill or be killed

00:07:45.500 --> 00:07:47.920
environment of unbridled capitalism,

00:07:47.920 --> 00:07:50.100
and that poor whites should be enslaved

00:07:50.100 --> 00:07:52.490
in addition to people of African descent

00:07:52.490 --> 00:07:54.220
in order to protect them from being

00:07:54.220 --> 00:07:56.170
eaten alive in the free market.

00:07:56.170 --> 00:07:58.830
In looking at these economic, social,

00:07:58.830 --> 00:08:01.830
and ideological differences
between the North and South,

00:08:01.830 --> 00:08:04.290
it's clear that by the 1850s there was

00:08:04.290 --> 00:08:07.140
really a clash of cultures going on.

00:08:07.140 --> 00:08:10.300
Would the United Stated
be an agricultural nation,

00:08:10.300 --> 00:08:12.100
or an industrial one?

00:08:12.100 --> 00:08:16.460
One where anyone, no matter
their color or place or birth,

00:08:16.460 --> 00:08:17.810
could climb the social ladder,

00:08:17.810 --> 00:08:20.230
or one where just a few deserved to

00:08:20.230 --> 00:08:22.270
enjoy all the blessings of liberty?

00:08:22.270 --> 00:08:24.600
In 1860, these questions would

00:08:24.600 --> 00:08:26.753
propel the country into civil war.


Enzyme reaction velocity and pH

WEBVTT
Kind: captions
Language: en

00:00:00.250 --> 00:00:01.260
- [Instructor] In this video,

00:00:01.260 --> 00:00:02.870
we're gonna talk about enzymes.

00:00:02.870 --> 00:00:05.830
And in particular, we're
going to talk about the effect

00:00:05.830 --> 00:00:10.830
of pH on enzymes, how acidic
or basic the environment is,

00:00:10.890 --> 00:00:13.890
how that affects enzyme activity.

00:00:13.890 --> 00:00:16.370
So just as a bit of a review,

00:00:16.370 --> 00:00:20.800
enzymes are molecules that help
catalyze various reactions,

00:00:20.800 --> 00:00:24.280
and they are all throughout
biological systems.

00:00:24.280 --> 00:00:28.350
Most enzymes are proteins,
large proteins oftentimes,

00:00:28.350 --> 00:00:30.650
made up of chains of amino acids.

00:00:30.650 --> 00:00:33.130
And so I could draw a chain of amino acid,

00:00:33.130 --> 00:00:35.680
where each of these circles
represents an amino acid.

00:00:35.680 --> 00:00:38.220
And the primary structure
is just a sequence

00:00:38.220 --> 00:00:41.520
of the amino acids, but there
is also a secondary structure

00:00:41.520 --> 00:00:46.250
on how this amino acid
backbone interacts with itself.

00:00:46.250 --> 00:00:49.450
And a lot of that is
based on hydrogen bonding.

00:00:49.450 --> 00:00:51.630
So that amino acid and that amino acid,

00:00:51.630 --> 00:00:54.880
maybe it forms some type of hydrogen bond.

00:00:54.880 --> 00:00:57.740
And just as a review, a
hydrogen bond is an interaction

00:00:57.740 --> 00:01:02.430
between hydrogen and a
more electronegative atom.

00:01:02.430 --> 00:01:05.080
So for example, we've seen this in water.

00:01:05.080 --> 00:01:09.860
Let me draw a couple of water
molecules right over here.

00:01:09.860 --> 00:01:11.530
And this is all review.

00:01:11.530 --> 00:01:13.320
In water, you have these covalent bonds

00:01:13.320 --> 00:01:15.310
between the oxygen and the hydrogen.

00:01:15.310 --> 00:01:17.520
So arguably, they're
sharing the electrons.

00:01:17.520 --> 00:01:19.770
But because oxygen is
more electronegative,

00:01:19.770 --> 00:01:21.810
it likes to hog the electrons more,

00:01:21.810 --> 00:01:24.170
the electrons spend more
time around the oxygens.

00:01:24.170 --> 00:01:26.860
So the oxygen end of a water molecule

00:01:26.860 --> 00:01:28.830
gets a partially negative charge,

00:01:28.830 --> 00:01:31.230
and then the hydrogen
ends of a water molecule

00:01:31.230 --> 00:01:33.640
get a partially positive,

00:01:33.640 --> 00:01:35.780
partially positive charge.

00:01:35.780 --> 00:01:39.890
This is the Greek lowercase
delta for partially,

00:01:39.890 --> 00:01:42.480
partial charge is what
it's typically used for.

00:01:42.480 --> 00:01:45.130
And so the partially negative
ends would be attracted

00:01:45.130 --> 00:01:47.550
to the partially positive
ends of another molecule,

00:01:47.550 --> 00:01:49.360
and that's what hydrogen bonds are.

00:01:49.360 --> 00:01:51.090
It's not always between
hydrogen and oxygen.

00:01:51.090 --> 00:01:53.640
In fact, oftentimes it's
between hydrogen and nitrogen,

00:01:53.640 --> 00:01:56.480
which is another electronegative atom.

00:01:56.480 --> 00:01:59.110
And these hydrogen bonds,
not only do they help define

00:01:59.110 --> 00:02:01.120
the secondary structure of the proteins,

00:02:01.120 --> 00:02:03.190
which helps to find the
shape of the protein,

00:02:03.190 --> 00:02:06.040
they can also interact with
the substrate of the protein,

00:02:06.040 --> 00:02:07.550
the things that the protein's

00:02:07.550 --> 00:02:10.180
trying to catalyze reactions on.

00:02:10.180 --> 00:02:11.960
So for example, if that's the substrate,

00:02:11.960 --> 00:02:13.850
and I'm just doing it as a big red circle,

00:02:13.850 --> 00:02:16.060
parts of it might form hydrogen bonds

00:02:16.060 --> 00:02:18.080
with the enzyme itself.

00:02:18.080 --> 00:02:21.900
And if you want to see a
more complex picture of that,

00:02:21.900 --> 00:02:24.290
this is a detailed schematic

00:02:24.290 --> 00:02:27.450
of a substrate interacting with an enzyme,

00:02:27.450 --> 00:02:30.540
where what you see in, circled in yellow,

00:02:30.540 --> 00:02:31.970
that is the substrate here.

00:02:31.970 --> 00:02:33.890
And you see these dotted lines,

00:02:33.890 --> 00:02:35.460
those are the hydrogen bonds.

00:02:35.460 --> 00:02:37.190
So you could see a hydrogen bond

00:02:37.190 --> 00:02:38.840
between a hydrogen and a nitrogen,

00:02:38.840 --> 00:02:41.830
a hydrogen bond between
an oxygen and a hydrogen.

00:02:41.830 --> 00:02:44.050
And so the yellow part is a substrate.

00:02:44.050 --> 00:02:46.060
And all the stuff that's
wrapping around it,

00:02:46.060 --> 00:02:48.620
that is the enzyme itself.

00:02:48.620 --> 00:02:52.170
So with that out of the way,
how does pH play into it?

00:02:52.170 --> 00:02:55.370
Well, we just have to
remind ourselves what pH is.

00:02:55.370 --> 00:02:58.450
pH, which is often viewed
as the power of hydrogen,

00:02:58.450 --> 00:03:00.280
that's where the p comes from,

00:03:00.280 --> 00:03:03.120
is the negative log, or at
least the way it's introduced

00:03:03.120 --> 00:03:04.780
in many introductory chemistry class,

00:03:04.780 --> 00:03:08.250
the negative log of the hydrogen

00:03:08.250 --> 00:03:10.000
ion concentration.

00:03:10.000 --> 00:03:13.930
And a hydrogen ion is
essentially a proton.

00:03:13.930 --> 00:03:16.630
Well, how would this
affect an enzyme's shape

00:03:16.630 --> 00:03:19.620
and its ability to interact
with the substrate,

00:03:19.620 --> 00:03:22.600
the thing that it's trying to act on?

00:03:22.600 --> 00:03:23.890
Well, if you have a bunch of,

00:03:23.890 --> 00:03:25.930
depending on how many hydrogen ions

00:03:25.930 --> 00:03:27.870
you have floating around,
and oftentimes it'll be

00:03:27.870 --> 00:03:30.870
in the form of hydronium,
which is a water molecule

00:03:30.870 --> 00:03:34.930
where the oxygen is bonded
to one extra hydrogen proton,

00:03:34.930 --> 00:03:37.480
well, it might mess with
these hydrogen bonds,

00:03:37.480 --> 00:03:41.610
where some of these hydrogen
protons usurp the bond

00:03:41.610 --> 00:03:45.030
with the negative end of
one of these molecules

00:03:45.030 --> 00:03:47.850
or repel some of the positive ends

00:03:47.850 --> 00:03:50.020
of some of these molecules
in a certain way.

00:03:50.020 --> 00:03:52.800
And so you could imagine
that different enzymes

00:03:52.800 --> 00:03:54.810
might have a different level of activity

00:03:54.810 --> 00:03:57.590
at different levels of pH,

00:03:57.590 --> 00:04:00.090
and that actually is the case.

00:04:00.090 --> 00:04:04.150
In fact, you'll often see a
diagram that looks like this.

00:04:04.150 --> 00:04:08.380
So in the vertical axis,
you will often see reaction,

00:04:08.380 --> 00:04:09.720
reaction

00:04:10.810 --> 00:04:11.963
velocity,

00:04:12.980 --> 00:04:15.630
where reaction velocity goes higher

00:04:15.630 --> 00:04:18.120
as we go higher in the vertical direction.

00:04:18.120 --> 00:04:21.450
And in this axis right over here,

00:04:21.450 --> 00:04:25.980
you might see our level of pH.

00:04:25.980 --> 00:04:29.670
And remember, pH, because you
have this negative out front,

00:04:29.670 --> 00:04:34.370
a high hydrogen ion concentration,

00:04:34.370 --> 00:04:35.930
because of this negative,

00:04:35.930 --> 00:04:39.220
that will give you a low pH,

00:04:39.220 --> 00:04:42.380
and that is associated with acidic,

00:04:42.380 --> 00:04:43.720
acidic environments.

00:04:43.720 --> 00:04:47.140
And a low hydrogen ion concentration,

00:04:47.140 --> 00:04:49.670
that's associated with a high pH,

00:04:49.670 --> 00:04:51.800
once again because of
this negative out front,

00:04:51.800 --> 00:04:55.890
and that's associated with
a more basic situation.

00:04:55.890 --> 00:04:58.330
And if your pH is around seven,

00:04:58.330 --> 00:05:00.290
then that would be a neutral situation.

00:05:00.290 --> 00:05:04.250
But different enzymes'
activities peak at different pHs.

00:05:04.250 --> 00:05:07.200
So for example, you might
have an enzyme like this

00:05:07.200 --> 00:05:10.580
whose activity peaks at a pH of,

00:05:10.580 --> 00:05:13.610
let's say this is right
over here, a pH of four,

00:05:13.610 --> 00:05:15.400
which is relatively acidic.

00:05:15.400 --> 00:05:17.960
And you would typically
see this type of an enzyme

00:05:17.960 --> 00:05:19.770
in, say, a place like the stomach,

00:05:19.770 --> 00:05:21.800
which is a very acidic environment.

00:05:21.800 --> 00:05:23.970
And then you might see other enzymes

00:05:23.970 --> 00:05:27.320
that actually don't do too
well in an acidic environment,

00:05:27.320 --> 00:05:31.400
but do quite well in a
more neutral environment.

00:05:31.400 --> 00:05:36.400
So for example, this peak might
be at, say, a pH of seven.

00:05:36.610 --> 00:05:38.060
And then you might have other enzymes

00:05:38.060 --> 00:05:40.000
that do better in a basic environment.

00:05:40.000 --> 00:05:43.010
And we actually do see
this in the human body.

00:05:43.010 --> 00:05:44.130
For example, lipase,

00:05:44.130 --> 00:05:47.120
which is an enzyme that breaks down fat,

00:05:47.120 --> 00:05:48.530
when it's found in the stomach,

00:05:48.530 --> 00:05:50.770
that particular version of lipase,

00:05:50.770 --> 00:05:53.350
it actually has optimum
activity closer to this,

00:05:53.350 --> 00:05:56.380
at a pH of roughly four or five.

00:05:56.380 --> 00:05:59.460
While lipase that is
secreted from the pancreas,

00:05:59.460 --> 00:06:01.860
which acts in the small intestines,

00:06:01.860 --> 00:06:05.190
which is a more neutral
environment or even slightly basic,

00:06:05.190 --> 00:06:09.000
its optimal activity is at a pH of eight.

00:06:09.000 --> 00:06:10.670
So I will leave you there.

00:06:10.670 --> 00:06:14.410
Big picture is, is that a
lot of an enzyme's shape

00:06:14.410 --> 00:06:16.970
or its ability to
interact with a substrate

00:06:16.970 --> 00:06:19.650
is based on hydrogen bonds.

00:06:19.650 --> 00:06:23.100
And so you can imagine hydrogen
bonds could be influenced

00:06:23.100 --> 00:06:25.560
by hydrogen ion concentration.

00:06:25.560 --> 00:06:28.640
And so because of that,
depending on your enzyme

00:06:28.640 --> 00:06:30.980
and sometimes the substrate
that you're dealing with,

00:06:30.980 --> 00:06:33.490
you might have different
reaction velocities

00:06:33.490 --> 00:06:35.060
at different pHs,

00:06:35.060 --> 00:06:37.840
with some enzymes doing
better in acidic environments

00:06:37.840 --> 00:06:39.620
and other enzymes doing better

00:06:39.620 --> 00:06:42.173
in neutral or basic environments.


Increased politicization of the Supreme Court

WEBVTT
Kind: captions
Language: en

00:00:00.280 --> 00:00:03.461
- In your mind, why is the
Supreme Court important?

00:00:03.461 --> 00:00:05.010
- Well the Supreme Court is important

00:00:05.010 --> 00:00:07.940
for the original
founders' reasons or that,

00:00:07.940 --> 00:00:09.710
it was like all American institutions

00:00:09.710 --> 00:00:11.020
there were ideas the founders had

00:00:11.020 --> 00:00:14.264
and then John Marshall,
an important justice,

00:00:14.264 --> 00:00:17.390
created the office by the
practice of the office

00:00:17.390 --> 00:00:20.570
and it is important
because the court is where

00:00:20.570 --> 00:00:23.600
America's thorniest
questions go to be resolved.

00:00:23.600 --> 00:00:25.640
They haven't been resolved
in the executive branch

00:00:25.640 --> 00:00:28.040
and the legislative
branch and so the court

00:00:28.040 --> 00:00:30.370
has to take them up and that is where

00:00:30.370 --> 00:00:32.330
the court goes back to
those first principles.

00:00:32.330 --> 00:00:34.090
Again, why we study American history.

00:00:34.090 --> 00:00:36.570
What exactly was the
outline for how the country

00:00:36.570 --> 00:00:39.730
is supposed to behave and are
we staying within that outline

00:00:39.730 --> 00:00:41.310
and those series of ideals?

00:00:41.310 --> 00:00:43.318
It goes back to the very
beginning ingredients

00:00:43.318 --> 00:00:44.370
of America.

00:00:44.370 --> 00:00:47.730
So, the court is a test always
of whether what we're doing

00:00:47.730 --> 00:00:50.660
now is in keeping with
what we were supposed to do

00:00:50.660 --> 00:00:51.744
at the founding of the country.

00:00:51.744 --> 00:00:54.610
The reason it has become
so important recently

00:00:54.610 --> 00:00:58.010
is that the court ends up
doing a lot more than it was

00:00:58.010 --> 00:01:00.340
ever supposed to do because of weakness

00:01:00.340 --> 00:01:02.910
in the executive branch
and the legislative branch

00:01:02.910 --> 00:01:05.250
and so a lot of people are
now looking to the court

00:01:05.250 --> 00:01:08.690
to solve problems that
should actually be handled

00:01:08.690 --> 00:01:09.977
by the people's representatives.

00:01:09.977 --> 00:01:11.496
The judges are not elected.

00:01:11.496 --> 00:01:13.879
They are in there for
life at the Supreme Court

00:01:13.879 --> 00:01:16.320
through the process of
the president with advice

00:01:16.320 --> 00:01:18.540
and consent by the Senate
but they are not elected

00:01:18.540 --> 00:01:20.410
and this was supposed to
be a republic in which

00:01:20.410 --> 00:01:23.790
the elected representatives
were the ones making the laws.

00:01:23.790 --> 00:01:25.400
But we've shifted away from that

00:01:25.400 --> 00:01:27.410
and so the court is now making decisions

00:01:27.410 --> 00:01:29.636
that can affect people's
lives and a generation

00:01:29.636 --> 00:01:34.280
and not be changed as easily
as say a piece of legislation

00:01:34.280 --> 00:01:38.220
which can be vetoed, amended,
superseded by another piece

00:01:38.220 --> 00:01:39.390
of legislation.

00:01:39.390 --> 00:01:42.960
It's really permanent
changes in the American life.

00:01:42.960 --> 00:01:44.480
- So my understanding is
that the Supreme Court

00:01:44.480 --> 00:01:45.889
should be above politics.

00:01:45.889 --> 00:01:49.140
To what degree is that actually the case?

00:01:49.140 --> 00:01:51.090
- Well the Supreme Court had lots of...

00:01:52.300 --> 00:01:53.970
There have been times
where the Supreme Court

00:01:53.970 --> 00:01:55.450
when Andrew Jackson was president

00:01:55.450 --> 00:01:57.590
he tried to use the Supreme
Court to do what he wanted

00:01:57.590 --> 00:01:59.542
it to do and Franklin Delano Roosevelt

00:01:59.542 --> 00:02:02.540
tried to change the
functioning of the court

00:02:02.540 --> 00:02:03.884
because it kept knocking
down all the things

00:02:03.884 --> 00:02:05.710
he wanted to do.

00:02:05.710 --> 00:02:07.970
We've had moments where
there have been these spasms

00:02:07.970 --> 00:02:09.640
where presidents have
tried to get the court

00:02:09.640 --> 00:02:10.723
to do what they wanted.

00:02:10.723 --> 00:02:13.750
But in general, it was
the American tradition

00:02:13.750 --> 00:02:15.680
that the justices were
supposed to be picked

00:02:15.680 --> 00:02:17.060
if they were of good character

00:02:17.060 --> 00:02:19.050
and if they were of sound legal mind.

00:02:19.050 --> 00:02:21.784
If they had views on the manners related

00:02:21.784 --> 00:02:26.620
to the Constitution that
were sort of sound legally.

00:02:26.620 --> 00:02:29.242
But their politics weren't
supposed to be so important.

00:02:29.242 --> 00:02:33.328
What has happened is like so
much in modern American life

00:02:33.328 --> 00:02:36.260
is there has been an
intertwining of politics

00:02:36.260 --> 00:02:39.580
and the legal profession
so that now when presidents

00:02:39.580 --> 00:02:41.282
run for office they say,

00:02:41.282 --> 00:02:45.005
elect me so that I can put
in our kinds of judges.

00:02:45.005 --> 00:02:47.516
Which means that the
kind of judge you pick

00:02:47.516 --> 00:02:50.355
helps you with your
voters and if your voters

00:02:50.355 --> 00:02:52.688
want a very specific kind
of ideological judge,

00:02:52.688 --> 00:02:55.640
then the more ideological
the judge that you pick,

00:02:55.640 --> 00:02:58.560
the greater your voters
will be happy about you

00:02:58.560 --> 00:02:59.995
and that'll keep you in office.

00:02:59.995 --> 00:03:02.840
And that is true of the
senators advising and consenting

00:03:02.840 --> 00:03:04.590
on these decisions and
true of the presidents

00:03:04.590 --> 00:03:05.470
who pick them.

00:03:05.470 --> 00:03:07.427
Well that means that the
people who go into the office

00:03:07.427 --> 00:03:10.280
into the Supreme Court I should say

00:03:10.280 --> 00:03:13.050
end up being more
political than in the past.

00:03:13.050 --> 00:03:15.276
There was a period where
when an American president

00:03:15.276 --> 00:03:16.660
would pick a justice,

00:03:16.660 --> 00:03:20.170
that justice very often
would rule in a way that was

00:03:20.170 --> 00:03:22.285
totally the opposite of what the members

00:03:22.285 --> 00:03:24.350
of that president's party wanted.

00:03:24.350 --> 00:03:26.650
It happened repeatedly in American life

00:03:26.650 --> 00:03:28.510
and that was a symbol people thought

00:03:28.510 --> 00:03:30.820
of the idea that these
issues before the court

00:03:30.820 --> 00:03:32.350
were being weighed on their merits

00:03:32.350 --> 00:03:35.090
and had nothing to do
with the ideological views

00:03:35.090 --> 00:03:36.490
of the judge weighing them.

00:03:36.490 --> 00:03:39.580
Now, where you sit on a particular issue

00:03:39.580 --> 00:03:42.330
is often determined by where
you came from politically.


Property rights in a market system

WEBVTT
Kind: captions
Language: en

00:00:00.940 --> 00:00:01.880
- [Instructor] In this
video we're going to

00:00:01.880 --> 00:00:03.900
talk about an idea that's crucial

00:00:03.900 --> 00:00:06.270
to the proper functioning of an economy

00:00:06.270 --> 00:00:08.170
under a market-based system.

00:00:08.170 --> 00:00:10.340
And that's the idea of property rights,

00:00:10.340 --> 00:00:13.320
and it's just the idea
that everyone agrees on

00:00:13.320 --> 00:00:15.560
who owns what and what can they do

00:00:15.560 --> 00:00:16.720
with that property?

00:00:16.720 --> 00:00:18.520
And for many of us who live in a part

00:00:18.520 --> 00:00:20.660
of the world with strong property rights,

00:00:20.660 --> 00:00:22.420
we take all of that for granted.

00:00:22.420 --> 00:00:24.130
We know who owns that house

00:00:24.130 --> 00:00:26.230
and what they have the
right to do with that house

00:00:26.230 --> 00:00:28.000
and if they were to sell that house,

00:00:28.000 --> 00:00:29.810
how that would occur,

00:00:29.810 --> 00:00:31.230
but in some parts of the world

00:00:31.230 --> 00:00:32.530
or in some parts of history,

00:00:32.530 --> 00:00:33.980
that wasn't so clear.

00:00:33.980 --> 00:00:35.570
Someone might say they own the house,

00:00:35.570 --> 00:00:37.940
but then another person
might live in that house

00:00:37.940 --> 00:00:39.640
and they say well I've been
living here for 10 years,

00:00:39.640 --> 00:00:41.820
it's my house now, deal with it.

00:00:41.820 --> 00:00:44.470
Or they might go hire some
thugs to say hey owner

00:00:44.470 --> 00:00:48.050
sell me the house for
less than the market value

00:00:48.050 --> 00:00:50.020
otherwise we're going
to hurt you in some way

00:00:50.020 --> 00:00:51.770
and so in some ways they're infringing

00:00:51.770 --> 00:00:52.710
on those property rights

00:00:52.710 --> 00:00:54.310
or the government might
just come in and say

00:00:54.310 --> 00:00:57.090
we're gonna take that property
from you because we want it

00:00:57.090 --> 00:01:00.610
and in those situations property
rights would be weakened,

00:01:00.610 --> 00:01:01.680
and what we're going to do

00:01:01.680 --> 00:01:02.970
is a little bit of a thought experiment

00:01:02.970 --> 00:01:04.720
to see why it's so crucial

00:01:04.720 --> 00:01:07.490
for the proper functioning
of a market economy.

00:01:07.490 --> 00:01:10.400
And so let's stick with the house analogy.

00:01:10.400 --> 00:01:12.646
So let's say that we have some blue houses

00:01:12.646 --> 00:01:16.250
in our economy that look like that.

00:01:16.250 --> 00:01:19.650
Let's say it's owned by
this person right over here.

00:01:19.650 --> 00:01:22.000
Let's say we have some pink houses

00:01:22.000 --> 00:01:23.670
that look like that.

00:01:23.670 --> 00:01:26.260
Let's say it's owned by
that person right over there

00:01:26.260 --> 00:01:29.500
and let's say that we
have some orange houses

00:01:29.500 --> 00:01:31.120
that look something like that.

00:01:31.120 --> 00:01:33.070
They have some kind of arch on the top

00:01:33.070 --> 00:01:35.480
and let's say it's owned
by something like this,

00:01:35.480 --> 00:01:37.520
and let's say these
people are all interested

00:01:37.520 --> 00:01:38.440
in selling their house.

00:01:38.440 --> 00:01:40.320
Maybe they're downsizing
or they're retiring

00:01:40.320 --> 00:01:41.830
or they're moving someplace else.

00:01:41.830 --> 00:01:44.520
And so there's a market
of potential buyers.

00:01:44.520 --> 00:01:49.030
So let me draw the buyers right over here

00:01:49.030 --> 00:01:51.530
and so there might be some people

00:01:51.530 --> 00:01:54.390
and if we have properly
functioning property rights,

00:01:54.390 --> 00:01:55.350
there might be some people

00:01:55.350 --> 00:01:58.370
who are really interested
in the blue house

00:01:58.370 --> 00:01:59.950
and so whoever is willing

00:01:59.950 --> 00:02:02.240
to pay the most for that
blue house will get it

00:02:02.240 --> 00:02:04.130
and so let's say that this person

00:02:04.130 --> 00:02:06.740
is willing to pay I
would say one dollar sign

00:02:06.740 --> 00:02:09.070
for the house and so the ownership

00:02:09.070 --> 00:02:11.030
of the house will go to that person.

00:02:11.030 --> 00:02:12.510
Same thing for the pink houses.

00:02:12.510 --> 00:02:13.930
Maybe this person right over here

00:02:13.930 --> 00:02:16.450
is the person who really
likes the pink houses.

00:02:16.450 --> 00:02:18.630
They pay a different price,
maybe a little bit more.

00:02:18.630 --> 00:02:20.630
I'll do two dollar
signs to represent that,

00:02:20.630 --> 00:02:24.170
and then they will get title to the house

00:02:24.170 --> 00:02:26.210
and maybe a ton of people
are really interested

00:02:26.210 --> 00:02:27.620
in these arched houses

00:02:27.620 --> 00:02:30.380
and maybe they bid for it
and the bidding keeps going

00:02:30.380 --> 00:02:31.280
higher and higher and higher

00:02:31.280 --> 00:02:32.540
and this person wins at the end

00:02:32.540 --> 00:02:34.540
and they have to pay up a lot

00:02:34.540 --> 00:02:39.540
for that orange house
that they get title for,

00:02:39.720 --> 00:02:42.010
and let's just assume
that for whatever reason,

00:02:42.010 --> 00:02:44.040
that they're all about
the same cost to build.

00:02:44.040 --> 00:02:46.460
Well what would happen
in this market then?

00:02:46.460 --> 00:02:49.350
Well home builders or
even people in other types

00:02:49.350 --> 00:02:50.500
of houses will say wow,

00:02:50.500 --> 00:02:53.010
I can get a lot more for the orange house.

00:02:53.010 --> 00:02:55.830
The market is giving us a price signal.

00:02:55.830 --> 00:02:59.060
So this right over here,
this is a price signal.

00:02:59.060 --> 00:03:01.020
In fact, they're all price signals,

00:03:01.020 --> 00:03:02.100
and when you take 'em together,

00:03:02.100 --> 00:03:03.050
you're saying, hey, I get more

00:03:03.050 --> 00:03:04.630
for an orange house than a blue house

00:03:04.630 --> 00:03:07.460
and so maybe if they all
cost the same to build

00:03:07.460 --> 00:03:10.250
we'll start producing more
of these orange houses.

00:03:10.250 --> 00:03:13.680
So builders will produce
more of these orange houses

00:03:13.680 --> 00:03:16.390
and maybe some people might
remodel their blue houses

00:03:16.390 --> 00:03:18.930
to have these orange arches on 'em,

00:03:18.930 --> 00:03:20.490
and so you could imagine that might happen

00:03:20.490 --> 00:03:21.350
from the price signal

00:03:21.350 --> 00:03:24.210
because it's clear that that's
where users preferences are.

00:03:24.210 --> 00:03:26.480
That's where the demand is,

00:03:26.480 --> 00:03:29.570
but now let's imagine a
slightly more dystopian world

00:03:29.570 --> 00:03:32.210
and this actually is what
much of human history was

00:03:32.210 --> 00:03:35.590
and even some significant
parts of the world today

00:03:35.590 --> 00:03:37.770
where there aren't clear property rights.

00:03:37.770 --> 00:03:41.510
When this person says that
they have this house for sale,

00:03:41.510 --> 00:03:43.580
these people are like
is it really your house?

00:03:43.580 --> 00:03:46.050
And then this person comes
along and says no it's my house

00:03:46.050 --> 00:03:48.480
and I have this proof that
my grandfather owned it

00:03:48.480 --> 00:03:50.190
and he never sold it to your grandfather

00:03:50.190 --> 00:03:53.490
and then this person
says I have a lot of guns

00:03:53.490 --> 00:03:55.340
and I don't care what y'all say

00:03:55.340 --> 00:03:58.030
and what paperwork you have,
but I'm taking the house.

00:03:58.030 --> 00:04:00.610
Well how much would this
person be willing to pay

00:04:00.610 --> 00:04:03.750
this person right over
here in that circumstance?

00:04:03.750 --> 00:04:05.970
And so this person is much less likely

00:04:05.970 --> 00:04:07.500
to get these three dollar signs

00:04:07.500 --> 00:04:09.460
This person said hey, this is
kind of a risky investment.

00:04:09.460 --> 00:04:12.030
I don't really know if I
take title from this person

00:04:12.030 --> 00:04:13.390
whether it's still my house.

00:04:13.390 --> 00:04:15.090
So they're not willing to
give three dollar signs,

00:04:15.090 --> 00:04:17.070
they're only willing
to give one dollar sign

00:04:17.070 --> 00:04:18.180
or maybe no dollar signs.

00:04:18.180 --> 00:04:19.970
Maybe this house doesn't even sell.

00:04:19.970 --> 00:04:22.240
Well then the price
signals have broken down,

00:04:22.240 --> 00:04:24.530
and so then in this
market people will tell me

00:04:24.530 --> 00:04:27.540
maybe we'll build more of
the arched orange houses

00:04:27.540 --> 00:04:29.510
because that's what the market demands

00:04:29.510 --> 00:04:30.930
and so you can quickly see

00:04:30.930 --> 00:04:33.390
that when property rights break down,

00:04:33.390 --> 00:04:34.740
the market system breaks down

00:04:34.740 --> 00:04:37.990
'cause the market system
is all about people using

00:04:37.990 --> 00:04:39.710
price to figure out how

00:04:39.710 --> 00:04:41.070
much they're willing to pay for things

00:04:41.070 --> 00:04:43.320
but that assumes that
when you get something

00:04:43.320 --> 00:04:44.380
that it's really yours,

00:04:44.380 --> 00:04:45.590
that it's not going to be disputed

00:04:45.590 --> 00:04:49.060
and the person you're buying
from really has ownership

00:04:49.060 --> 00:04:50.530
and this break down would often

00:04:50.530 --> 00:04:53.370
be characterized as a market failure.

00:04:53.370 --> 00:04:55.290
Now you could say okay there's other types

00:04:55.290 --> 00:04:57.090
of systems that we've talked
about in other videos.

00:04:57.090 --> 00:04:58.860
We talk about command economies

00:04:58.860 --> 00:05:00.843
and in the extreme in a command economy,

00:05:00.843 --> 00:05:05.280
you have no private ownership of things

00:05:05.280 --> 00:05:08.400
and so you might say
maybe that is a solution

00:05:08.400 --> 00:05:10.450
to this property rights problem,

00:05:10.450 --> 00:05:11.880
but command economies have

00:05:11.880 --> 00:05:14.080
significant problems of their own.

00:05:14.080 --> 00:05:16.820
In fact, very few of them or
really none of them in history

00:05:16.820 --> 00:05:18.690
have proven to really work

00:05:18.690 --> 00:05:21.900
because they have a
major incentive problem

00:05:21.900 --> 00:05:23.435
because if you're just being told

00:05:23.435 --> 00:05:25.830
what to build by the government,

00:05:25.830 --> 00:05:27.970
you're told how to build
it by the government,

00:05:27.970 --> 00:05:30.220
you're told who that gets
it by the government.

00:05:30.220 --> 00:05:31.290
There's very little incentive

00:05:31.290 --> 00:05:33.400
to try to innovate, to try to build more,

00:05:33.400 --> 00:05:35.110
to invest, or whatever else,

00:05:35.110 --> 00:05:37.980
and we talk about that in other videos.

00:05:37.980 --> 00:05:39.350
So I will let you go there.

00:05:39.350 --> 00:05:41.260
This is just an
introduction to think about

00:05:41.260 --> 00:05:42.830
this idea of property rights

00:05:42.830 --> 00:05:46.000
and ask your parents or talk
around or if you are a parent,

00:05:46.000 --> 00:05:48.650
look at the world of how
much infrastructure we have

00:05:48.650 --> 00:05:50.200
in a society like the United States

00:05:50.200 --> 00:05:51.800
or in much of the world today

00:05:51.800 --> 00:05:53.913
to enforce property rights.


Introduction to utility

WEBVTT
Kind: captions
Language: en

00:00:00.270 --> 00:00:01.103
- [Instructor] We are now

00:00:01.103 --> 00:00:02.360
going to introduce ourselves

00:00:02.360 --> 00:00:06.310
to the idea of Utility in Economics.

00:00:06.310 --> 00:00:07.760
Now in everyday language,

00:00:07.760 --> 00:00:09.750
if someone says what's
the Utility of that?

00:00:09.750 --> 00:00:12.250
They're usually saying
what's the usefulness

00:00:12.250 --> 00:00:13.260
of doing that.

00:00:13.260 --> 00:00:14.663
And Utility in Economics

00:00:14.663 --> 00:00:17.220
takes that view of Utility

00:00:17.220 --> 00:00:18.550
and extends that a little bit.

00:00:18.550 --> 00:00:20.640
You could view Utility in Economics

00:00:20.640 --> 00:00:23.810
as a measure of usefulness,

00:00:23.810 --> 00:00:28.570
usefulness, worth, value.

00:00:28.570 --> 00:00:30.100
Some economists will even say

00:00:30.100 --> 00:00:31.720
it's a measure of happiness

00:00:31.720 --> 00:00:34.940
'cause things that might
not have a practical use

00:00:34.940 --> 00:00:38.060
can still have Utility
to them in Economics

00:00:38.060 --> 00:00:39.930
because they're giving
you some satisfaction

00:00:39.930 --> 00:00:41.130
or some happiness,

00:00:41.130 --> 00:00:43.740
or I'll even write that over here.

00:00:43.740 --> 00:00:47.190
And as we'll see, it is
something that economists

00:00:47.190 --> 00:00:50.360
try to measure or try to quantify,

00:00:50.360 --> 00:00:53.600
and they do it with just Utility units.

00:00:53.600 --> 00:00:56.310
So let's see a tangible example of that.

00:00:56.310 --> 00:00:58.140
So let's say you wanted to think about

00:00:58.140 --> 00:01:01.210
your Utility from scoops of ice cream.

00:01:01.210 --> 00:01:03.120
So if we say, let's make a col,

00:01:03.120 --> 00:01:04.550
let's make a table here.

00:01:04.550 --> 00:01:07.030
So number of scoops,

00:01:07.030 --> 00:01:08.800
that'll be in my left column,

00:01:08.800 --> 00:01:10.640
and then on my right column,

00:01:10.640 --> 00:01:12.950
let's think about Total Utility,

00:01:15.600 --> 00:01:17.950
and I will do it in utils.

00:01:17.950 --> 00:01:22.000
You could view that as
your unit of Utility.

00:01:22.000 --> 00:01:24.043
And let me put my columns in here.

00:01:25.450 --> 00:01:27.920
So, there we go.

00:01:27.920 --> 00:01:28.753
And so let's say

00:01:28.753 --> 00:01:31.610
if I have zero scoops of ice cream,

00:01:31.610 --> 00:01:32.443
well you might guess

00:01:32.443 --> 00:01:34.010
what my Utility is going to be,

00:01:34.010 --> 00:01:36.500
it is going to be zero.

00:01:36.500 --> 00:01:39.270
Now what if I have one scoop of ice cream?

00:01:39.270 --> 00:01:40.103
Well let's just say that

00:01:40.103 --> 00:01:42.550
that is 80 Utility units.

00:01:42.550 --> 00:01:43.480
And I know what you're thinking,

00:01:43.480 --> 00:01:46.590
Sal, where did you come
with 80 Utility units?

00:01:46.590 --> 00:01:49.220
And this is really just
an arbitrary number

00:01:49.220 --> 00:01:50.720
that I'm throwing down here.

00:01:50.720 --> 00:01:53.090
What's more important is what this is

00:01:53.090 --> 00:01:56.140
relative to my Utility for other things.

00:01:56.140 --> 00:01:59.100
So, for example, using this scale,

00:01:59.100 --> 00:02:01.770
if I said two scoops of ice cream,

00:02:01.770 --> 00:02:03.967
my Total Utility is 140.

00:02:05.470 --> 00:02:07.760
80 and 140 aren't what matter.

00:02:07.760 --> 00:02:11.030
What matters is the ratio between the two.

00:02:11.030 --> 00:02:12.260
So if I said my Utility

00:02:12.260 --> 00:02:14.770
for one scoop of ice cream was 800,

00:02:14.770 --> 00:02:16.960
then, if this ratio is true,

00:02:16.960 --> 00:02:18.700
then for two scoops of ice cream,

00:02:18.700 --> 00:02:21.520
my Total Utility would be 1,400.

00:02:21.520 --> 00:02:24.750
It could be eight million and 14 million.

00:02:24.750 --> 00:02:27.540
What matters is the relative Utility.

00:02:27.540 --> 00:02:30.010
I just happened to anchor on one scoop

00:02:30.010 --> 00:02:33.420
gives me eight units, Total Utility units.

00:02:33.420 --> 00:02:34.320
But let's keep going.

00:02:34.320 --> 00:02:36.370
If we go with this scale,

00:02:36.370 --> 00:02:37.829
then three scoops of ice cream,

00:02:37.829 --> 00:02:39.800
let's say that this gives me

00:02:39.800 --> 00:02:41.767
180 units of Utility.

00:02:41.767 --> 00:02:43.090
And I know what you're saying.

00:02:43.090 --> 00:02:44.480
Even if you get the ratio right,

00:02:44.480 --> 00:02:45.320
how do you even know that

00:02:45.320 --> 00:02:46.750
this is the right ratio?

00:02:46.750 --> 00:02:50.130
Well, economists will
debate how to measure this,

00:02:50.130 --> 00:02:52.380
but there might be ways
that you could measure it

00:02:52.380 --> 00:02:53.270
maybe with dollars,

00:02:53.270 --> 00:02:54.750
with what people are willing to pay,

00:02:54.750 --> 00:02:56.260
and then you can get the ratios.

00:02:56.260 --> 00:02:57.510
You could survey people.

00:02:57.510 --> 00:02:59.180
You could say on a scale of 10, one to 10,

00:02:59.180 --> 00:03:00.650
how happy will it make you

00:03:00.650 --> 00:03:02.720
if you got one scoop of ice cream?

00:03:02.720 --> 00:03:04.300
What if you got two scoops of ice cream?

00:03:04.300 --> 00:03:05.133
What if you got three?

00:03:05.133 --> 00:03:07.290
And then you would wanna
get these ratios right.

00:03:07.290 --> 00:03:09.210
But, of course, it isn't an exact science,

00:03:09.210 --> 00:03:11.250
but people are trying to quantity this.

00:03:11.250 --> 00:03:12.830
Now let's just go to four.

00:03:12.830 --> 00:03:14.070
Four scoops of ice cream

00:03:14.070 --> 00:03:15.260
would give you a Total Utility,

00:03:15.260 --> 00:03:16.440
let's say we knew it would give you

00:03:16.440 --> 00:03:21.440
a Total Utility of 170.

00:03:22.210 --> 00:03:24.760
Now something interesting is happening.

00:03:24.760 --> 00:03:26.910
As you got more scoops of ice cream,

00:03:26.910 --> 00:03:29.200
from zero to one, from one to two,

00:03:29.200 --> 00:03:30.600
from two to three,

00:03:30.600 --> 00:03:34.520
it looks like you're getting more Utility,

00:03:34.520 --> 00:03:35.720
but then all of a sudden,

00:03:35.720 --> 00:03:37.110
when you have four scoops of ice cream,

00:03:37.110 --> 00:03:39.370
your Total Utility goes down a little bit.

00:03:39.370 --> 00:03:40.520
Maybe it's because

00:03:40.520 --> 00:03:42.270
people can't eat four scoops of ice cream

00:03:42.270 --> 00:03:43.480
and they say what do I do with that?

00:03:43.480 --> 00:03:44.330
And they just have all,

00:03:44.330 --> 00:03:46.170
they're left with a bowl
of melted ice cream.

00:03:46.170 --> 00:03:48.300
And so it doesn't give
them as much Utility,

00:03:48.300 --> 00:03:49.900
it makes them feel bad somehow

00:03:49.900 --> 00:03:51.990
as having three bowls of ice cream

00:03:51.990 --> 00:03:53.900
or three scoops of ice cream.

00:03:53.900 --> 00:03:55.500
Another thing to think about is

00:03:55.500 --> 00:03:58.410
how much does the Total Utility increase

00:03:58.410 --> 00:03:59.810
every time you get

00:03:59.810 --> 00:04:01.940
an incremental unit of that thing?

00:04:01.940 --> 00:04:03.660
And we'll talk about it in more depth

00:04:03.660 --> 00:04:06.691
in future videos, but that general idea

00:04:06.691 --> 00:04:09.380
of how much more Utility you get

00:04:09.380 --> 00:04:11.280
for that incremental unit.

00:04:11.280 --> 00:04:13.250
In Economics when we're talking about

00:04:13.250 --> 00:04:15.070
what happens on the increment,

00:04:15.070 --> 00:04:16.813
we use the word marginal a lot.

00:04:18.096 --> 00:04:21.233
Marginal Utility,

00:04:23.210 --> 00:04:24.733
sometimes abbreviated mu.

00:04:25.900 --> 00:04:29.330
And this would still be in Utility units.

00:04:29.330 --> 00:04:32.580
And so we could start with that first

00:04:32.580 --> 00:04:34.120
going from zero to one.

00:04:34.120 --> 00:04:35.860
I'll start with that
first scoop of ice cream.

00:04:35.860 --> 00:04:37.450
What's the marginal utility?

00:04:37.450 --> 00:04:40.560
Well it gave you an incremental 80 units

00:04:40.560 --> 00:04:43.740
of Utility, so the marginal utility is 80.

00:04:43.740 --> 00:04:46.000
Now what about that
second scoop of ice cream?

00:04:46.000 --> 00:04:47.320
Well we know when you had one,

00:04:47.320 --> 00:04:49.360
you had 80 Total Utility units,

00:04:49.360 --> 00:04:51.610
and now when you have two, you have 140,

00:04:51.610 --> 00:04:53.810
so that incremental second scoop

00:04:53.810 --> 00:04:55.760
gave you to go from 80 to 140,

00:04:55.760 --> 00:04:59.850
it gave you 60 extra units of Utility.

00:04:59.850 --> 00:05:01.710
So notice, you are really,

00:05:01.710 --> 00:05:03.710
it really increased your happiness or,

00:05:03.710 --> 00:05:05.470
you got a lot of value
out of that first scoop

00:05:05.470 --> 00:05:06.610
and you still got value

00:05:06.610 --> 00:05:07.480
outta that second scoop,

00:05:07.480 --> 00:05:08.890
but it's a little bit less

00:05:08.890 --> 00:05:10.730
because you're not maybe
just as not as hungry,

00:05:10.730 --> 00:05:12.040
you're getting a little bit tired

00:05:12.040 --> 00:05:12.890
of the ice cream.

00:05:12.890 --> 00:05:14.190
And then that continues to happen

00:05:14.190 --> 00:05:16.730
on that third scoop,
to go from 140 to 180,

00:05:16.730 --> 00:05:19.763
that third scoop gave
you 40 units of Utility.

00:05:20.730 --> 00:05:22.110
And then as we talked about,

00:05:22.110 --> 00:05:24.020
when you add on that fourth scoop,

00:05:24.020 --> 00:05:25.610
it didn't even add to your Total Utility,

00:05:25.610 --> 00:05:27.350
it took away from your Total Utility.

00:05:27.350 --> 00:05:29.640
So it actually had a
negative marginal utility.

00:05:29.640 --> 00:05:32.100
It is negative 10.

00:05:32.100 --> 00:05:34.690
That fourth scoop actually took away

00:05:34.690 --> 00:05:36.090
from your happiness.

00:05:36.090 --> 00:05:37.800
So I will leave you there.

00:05:37.800 --> 00:05:41.420
You have this idea of
Utility, Total Utility,

00:05:41.420 --> 00:05:43.240
and we also looked at Marginal Utility.

00:05:43.240 --> 00:05:44.350
And you see in this example,

00:05:44.350 --> 00:05:46.930
and this is typical, that Marginal Utility

00:05:46.930 --> 00:05:49.230
typically decreases as you get

00:05:49.230 --> 00:05:52.720
more and more units of that thing.

00:05:52.720 --> 00:05:53.840
And in future videos,

00:05:53.840 --> 00:05:56.330
we're going to use this
framework of Utility,

00:05:56.330 --> 00:05:58.220
Total Utility, Marginal Utility,

00:05:58.220 --> 00:05:59.740
to think about how folks

00:05:59.740 --> 00:06:02.050
might make rational decisions

00:06:02.050 --> 00:06:04.193
to optimize their Total Utility.


Accounting profit vs  economic profit

WEBVTT
Kind: captions
Language: en

00:00:01.010 --> 00:00:02.090
- [Instructor] Let's continue thinking

00:00:02.090 --> 00:00:05.610
about how rational agents make decisions.

00:00:05.610 --> 00:00:08.410
So here we're told that
Sally runs a business

00:00:08.410 --> 00:00:12.450
that only sells hamburgers
in a building she owns.

00:00:12.450 --> 00:00:15.770
Every month, they sell 5,000 hamburgers

00:00:15.770 --> 00:00:18.240
at $5 per hamburger.

00:00:18.240 --> 00:00:21.900
She spends $2 per hamburger
on supplies, bread, meat,

00:00:21.900 --> 00:00:23.310
lettuce, et cetera.

00:00:23.310 --> 00:00:28.150
She also pays Mike and
Raj each $2,500 per month

00:00:28.150 --> 00:00:30.100
to work at the restaurant.

00:00:30.100 --> 00:00:34.470
Finally, utilities cost $500 per month.

00:00:34.470 --> 00:00:36.820
Sally works full-time at the restaurant

00:00:36.820 --> 00:00:40.250
and keeps the accounting
profits for herself.

00:00:40.250 --> 00:00:43.460
What is the accounting
profit of the business?

00:00:43.460 --> 00:00:47.000
So pause this video and see
if you can figure that out.

00:00:47.000 --> 00:00:49.370
All right now let's think
about this together.

00:00:49.370 --> 00:00:51.900
We're gonna think about
it in terms of some

00:00:51.900 --> 00:00:55.580
of the types of costs we've
thought about in the past.

00:00:55.580 --> 00:00:58.430
So when we think about benefits,
and here we could think

00:00:58.430 --> 00:01:01.710
about it to a firm, although
it's fully owned by Sally,

00:01:01.710 --> 00:01:05.860
the benefit to a firm of
doing business is its revenue.

00:01:05.860 --> 00:01:08.510
So the total revenue that she collects,

00:01:08.510 --> 00:01:09.720
and everything we're gonna be doing

00:01:09.720 --> 00:01:11.913
is going to be per month,

00:01:12.930 --> 00:01:16.290
so her total revenue is going
to be her price times quantity

00:01:16.290 --> 00:01:21.100
so it's going to be 5,000
hamburgers at $5 per hamburger.

00:01:21.100 --> 00:01:24.740
So that is going to be $25,000.

00:01:24.740 --> 00:01:27.520
Once again, all of this
is going to be per month.

00:01:27.520 --> 00:01:30.100
So once again, we can view
this as the total benefit

00:01:30.100 --> 00:01:33.210
that the firm, that her
business, is getting.

00:01:33.210 --> 00:01:35.210
And now let's think about the costs.

00:01:35.210 --> 00:01:38.140
So first we could think about
the cost of her supplies.

00:01:38.140 --> 00:01:40.940
It's oftentimes referred
to costs of goods sold,

00:01:40.940 --> 00:01:42.870
but I'll just write supplies here.

00:01:42.870 --> 00:01:47.870
So costs, costs colon, so
let's put supplies, supplies.

00:01:50.400 --> 00:01:54.050
That would be 5,000 hamburgers
times $2 per hamburger,

00:01:54.050 --> 00:01:58.580
so that's a $10,000 cost, $10,000.

00:01:58.580 --> 00:02:02.350
Then she has the cost of her employees.

00:02:02.350 --> 00:02:04.860
So employees, I'll just write it,

00:02:04.860 --> 00:02:06.680
I'll abbreviate it like that.

00:02:06.680 --> 00:02:07.890
What's that going to be?

00:02:07.890 --> 00:02:10.876
Well she has two folks
at $2,500 per month each.

00:02:10.876 --> 00:02:15.876
So that's going to be $5,000,
two times $2,500, $5,000.

00:02:16.940 --> 00:02:21.350
And then last but not least,
she has her utilities.

00:02:21.350 --> 00:02:26.050
So utilities, let's do util for short.

00:02:26.050 --> 00:02:30.050
That's going to be $500 per month.

00:02:30.050 --> 00:02:34.340
And so from this we can
calculate the accounting profit.

00:02:34.340 --> 00:02:39.340
So we get the accounting
profit, accounting profit,

00:02:42.500 --> 00:02:47.277
is going to be 25,000 minus 15,500.

00:02:49.170 --> 00:02:54.170
That's going to be $9,500 per month.

00:02:54.210 --> 00:02:56.200
And she gets to keep all of this,

00:02:56.200 --> 00:02:58.530
and so this seems like a
pretty good amount of money

00:02:58.530 --> 00:02:59.530
to be earning.

00:02:59.530 --> 00:03:02.220
She's earning six figures a year.

00:03:02.220 --> 00:03:06.250
But the question is, is it
rational for her to do this?

00:03:06.250 --> 00:03:08.190
Well some of you might
be correctly thinking,

00:03:08.190 --> 00:03:10.850
well in order to determine
whether it's rational

00:03:10.850 --> 00:03:13.360
for her to continue running this business,

00:03:13.360 --> 00:03:16.710
we have to know what
the implicit costs are.

00:03:16.710 --> 00:03:20.380
Here we've only just looked
at the explicit costs,

00:03:20.380 --> 00:03:22.890
and the most important
of the implicit costs

00:03:22.890 --> 00:03:25.460
is the opportunity cost.

00:03:25.460 --> 00:03:28.000
And to factor that, we have to know,

00:03:28.000 --> 00:03:30.700
well maybe what she could've
rented her building out,

00:03:30.700 --> 00:03:33.120
if she wasn't running
this burger business,

00:03:33.120 --> 00:03:35.340
and maybe what she could do with her time

00:03:35.340 --> 00:03:37.530
if she wasn't working at
the business full-time.

00:03:37.530 --> 00:03:39.540
So we need a little bit more
information and let's see

00:03:39.540 --> 00:03:40.490
if we can get that.

00:03:43.350 --> 00:03:47.410
So now we are told that Sally
could rent out her building

00:03:47.410 --> 00:03:50.190
for $5,000 per month.

00:03:50.190 --> 00:03:54.110
She can also make $6,000
per month as an accountant.

00:03:54.110 --> 00:03:58.440
Based on this, what is the
economic profit of her business?

00:03:58.440 --> 00:04:01.190
So pause this video and see
if you can figure this out.

00:04:02.330 --> 00:04:03.830
Well one way to think about it is,

00:04:03.830 --> 00:04:05.880
we can start with our accounting profit

00:04:05.880 --> 00:04:08.400
and then subtract out
all the implicit costs,

00:04:08.400 --> 00:04:11.360
especially these opportunity
costs right over here.

00:04:11.360 --> 00:04:15.493
So her opportunity
cost, opportunity costs,

00:04:17.280 --> 00:04:19.850
are going to be per month,

00:04:19.850 --> 00:04:21.420
well if she doesn't run this business,

00:04:21.420 --> 00:04:24.210
she could rent out her
building for $5,000 per month

00:04:25.180 --> 00:04:27.360
and then if she wasn't
doing this full-time,

00:04:27.360 --> 00:04:30.117
she could make $6,000 per
month as an accountant,

00:04:30.117 --> 00:04:32.650
$6,000 right over there.

00:04:32.650 --> 00:04:37.417
And so her opportunity costs
are a total of $11,000.

00:04:38.630 --> 00:04:41.960
And so now her economic profit would be

00:04:41.960 --> 00:04:46.960
her total benefit minus her explicit costs

00:04:47.430 --> 00:04:50.460
minus her implicit costs.

00:04:50.460 --> 00:04:53.787
Her economic profit, economic profit,

00:04:57.580 --> 00:05:00.170
is going to be, well we
could start at the 9,500

00:05:00.170 --> 00:05:02.550
and subtract the 11,000,

00:05:02.550 --> 00:05:05.097
it is negative $1,500.

00:05:08.800 --> 00:05:11.430
It's important to realize,
because economic profit

00:05:11.430 --> 00:05:13.470
always factors in the explicit costs

00:05:13.470 --> 00:05:16.218
and then other potential implicit costs,

00:05:16.218 --> 00:05:19.150
economic profit will never be higher

00:05:19.150 --> 00:05:20.310
than accounting profit.

00:05:20.310 --> 00:05:22.290
And assuming there are
some implicit costs,

00:05:22.290 --> 00:05:25.950
it'll always be lower
than accounting profit.

00:05:25.950 --> 00:05:28.410
So now based on all of
what we've explored,

00:05:28.410 --> 00:05:31.310
is it rational for Sally
to continue running

00:05:31.310 --> 00:05:32.413
her burger business?

00:05:33.300 --> 00:05:35.830
Well based on the
information we've been given,

00:05:35.830 --> 00:05:38.030
it doesn't seem rational
for her to continue

00:05:38.030 --> 00:05:39.730
running her burger business.

00:05:39.730 --> 00:05:43.060
She makes $9,500 in accounting profit

00:05:43.060 --> 00:05:46.500
from the business, but
she's incurring $11,000

00:05:46.500 --> 00:05:48.470
of opportunity cost to do so.

00:05:48.470 --> 00:05:51.850
And that's what makes her
economic profit negative.

00:05:51.850 --> 00:05:53.490
This is not rational.

00:05:53.490 --> 00:05:55.310
Now if we had more information,

00:05:55.310 --> 00:05:57.500
maybe she hates being an accountant.

00:05:57.500 --> 00:06:00.680
Maybe there's a benefit for her working

00:06:00.680 --> 00:06:01.513
at the burger business.

00:06:01.513 --> 00:06:03.140
She has more flexibility with her time,

00:06:03.140 --> 00:06:04.980
she likes being self-employed,
she doesn't have

00:06:04.980 --> 00:06:07.450
to listen to her manager
tell her want to do.

00:06:07.450 --> 00:06:09.980
If that were the case,
then it would change

00:06:09.980 --> 00:06:12.820
the calculations some
because there would be

00:06:12.820 --> 00:06:16.360
an extra benefit from her
running her burger joint.

00:06:16.360 --> 00:06:18.656
But we don't know, and based
on the information we have,

00:06:18.656 --> 00:06:21.883
it doesn't seem rational
for her to continue.


Optimal decision-making and opportunity costs

WEBVTT
Kind: captions
Language: en

00:00:00.110 --> 00:00:01.230
- [Instructor] What we're
going to do in this video

00:00:01.230 --> 00:00:05.770
is think about optimal decision
making by rational agents.

00:00:05.770 --> 00:00:08.860
And it's just thinking
about how would a logical,

00:00:08.860 --> 00:00:11.430
someone with a lot of reasoning ability,

00:00:11.430 --> 00:00:12.950
make optimal decisions,

00:00:12.950 --> 00:00:16.360
make the best decisions for themselves?

00:00:16.360 --> 00:00:19.860
Well they would look at the
costs and benefits of a decision

00:00:19.860 --> 00:00:23.130
and they would try to do
the action that maximizes

00:00:23.130 --> 00:00:25.790
the difference between benefits and costs.

00:00:25.790 --> 00:00:28.500
So they would wanna maximize benefits,

00:00:28.500 --> 00:00:31.740
benefits minus costs.

00:00:31.740 --> 00:00:33.750
And this is an important
idea because I think

00:00:33.750 --> 00:00:36.830
all of us would like
to be rational agents,

00:00:36.830 --> 00:00:40.810
logical agents, making optimal decisions.

00:00:40.810 --> 00:00:43.430
Now when we think about
benefits and costs,

00:00:43.430 --> 00:00:45.670
benefits you might try
to quantify it somehow,

00:00:45.670 --> 00:00:46.860
maybe in terms of dollars.

00:00:46.860 --> 00:00:49.026
What's the benefit of say going to a movie

00:00:49.026 --> 00:00:51.220
or having some ice cream?

00:00:51.220 --> 00:00:54.190
And costs, we tend to
associate with a price,

00:00:54.190 --> 00:00:57.540
the cost of going to a
movie say might be $10.

00:00:57.540 --> 00:01:01.080
Those types of things are
known as explicit costs,

00:01:01.080 --> 00:01:04.090
when there's an explicit
price associated with it.

00:01:04.090 --> 00:01:08.020
But there's also something
known as implicit costs,

00:01:08.020 --> 00:01:12.490
and the most well-defined implicit cost

00:01:12.490 --> 00:01:15.690
is the idea of an opportunity cost.

00:01:15.690 --> 00:01:18.720
And the opportunity cost in economic terms

00:01:18.720 --> 00:01:23.720
is defined as the cost of
the next best alternative.

00:01:24.900 --> 00:01:27.360
So if I'm going to go to
a movie, there might be

00:01:27.360 --> 00:01:30.630
the explicit costs of
paying for the movie,

00:01:30.630 --> 00:01:32.290
but then there's the implicit cost.

00:01:32.290 --> 00:01:34.670
Maybe if I'm going to a movie,
that time I could've used

00:01:34.670 --> 00:01:35.720
for something else.

00:01:35.720 --> 00:01:38.090
Maybe I could've earned money somehow.

00:01:38.090 --> 00:01:41.130
And so a rational actor
would consider both of those

00:01:41.130 --> 00:01:44.200
and then compare them to the
benefit of going to the movie,

00:01:44.200 --> 00:01:46.360
and if that's what
maximizes the difference

00:01:46.360 --> 00:01:48.510
between benefits and
costs, well they might

00:01:48.510 --> 00:01:50.150
decide to do that.

00:01:50.150 --> 00:01:52.170
Now to make this a
little bit more tangible,

00:01:52.170 --> 00:01:54.763
let's look at that exact example.

00:01:55.720 --> 00:01:58.830
So right over here, we are told,

00:01:58.830 --> 00:02:01.890
suppose you have the choice
between going to a movie

00:02:01.890 --> 00:02:04.970
for three hours versus
working for three hours.

00:02:04.970 --> 00:02:07.480
Movie tickets cost $10.

00:02:07.480 --> 00:02:11.137
If you work, you can earn
$30 an hour mowing lawns,

00:02:11.137 --> 00:02:14.800
$12 an hour working in an ice cream shop,

00:02:14.800 --> 00:02:18.190
or $10 an hour weeding your aunt's garden.

00:02:18.190 --> 00:02:21.160
What is the opportunity
cost of going to a movie

00:02:21.160 --> 00:02:22.120
for three hours?

00:02:22.120 --> 00:02:24.150
And what is the total cost?

00:02:24.150 --> 00:02:26.900
So pause this video and see
if you can figure that out.

00:02:27.980 --> 00:02:29.950
All right well we just have
to go back to the definition.

00:02:29.950 --> 00:02:31.640
The opportunity cost is the cost

00:02:31.640 --> 00:02:34.240
of the next best alternative.

00:02:34.240 --> 00:02:39.200
So what is the next best
alternative to going to the movie?

00:02:39.200 --> 00:02:43.130
Well, I can make the most
money if I am mowing lawns,

00:02:43.130 --> 00:02:45.100
if I am mowing lawns.

00:02:45.100 --> 00:02:49.100
And so my opportunity cost
is going to be $30 an hour,

00:02:49.100 --> 00:02:52.020
and if I'm going to a movie,
that would've been three hours

00:02:52.020 --> 00:02:54.570
that I would not have
been able to mow lawns.

00:02:54.570 --> 00:02:56.870
And so my opportunity cost, I'll write OC,

00:02:56.870 --> 00:02:59.580
I'm not talking about Orange County,

00:02:59.580 --> 00:03:02.957
the opportunity cost right
over here is going to be

00:03:02.957 --> 00:03:05.370
$30 an hour times three hours,

00:03:05.370 --> 00:03:09.767
so 30 times three, which
is going to be a $90,

00:03:09.767 --> 00:03:12.370
$90 opportunity cost.

00:03:12.370 --> 00:03:14.220
Now some of you might be
saying, well what about

00:03:14.220 --> 00:03:16.990
the $12 an hour for an ice
cream shop or $10 an hour

00:03:16.990 --> 00:03:19.520
for weeding your aunt's garden?

00:03:19.520 --> 00:03:21.680
Well, those weren't the
next best alternative.

00:03:21.680 --> 00:03:25.020
The next best alternative
was mowing the lawn.

00:03:25.020 --> 00:03:26.640
Some people might be confused and say,

00:03:26.640 --> 00:03:29.000
okay I'm gonna add all of
these together per hour

00:03:29.000 --> 00:03:31.140
and multiply by three, but
you're not gonna be able

00:03:31.140 --> 00:03:32.440
to do all three of these things.

00:03:32.440 --> 00:03:34.720
You're going to have to pick one of them.

00:03:34.720 --> 00:03:38.160
And we're assuming that maybe
there aren't any extra costs

00:03:38.160 --> 00:03:42.350
that are not, maybe you get
extra tired from mowing lawns

00:03:42.350 --> 00:03:44.410
versus working in an ice cream shop,

00:03:44.410 --> 00:03:45.760
but we're trying to simplify things,

00:03:45.760 --> 00:03:48.530
so let's not get overly
complicated right now.

00:03:48.530 --> 00:03:51.730
So at a very face level
or at a high level,

00:03:51.730 --> 00:03:53.350
the next best alternative

00:03:53.350 --> 00:03:56.300
is making $30 an hour mowing lawns.

00:03:56.300 --> 00:03:58.370
So that would be the opportunity cost.

00:03:58.370 --> 00:04:00.270
Now what would be the total cost?

00:04:00.270 --> 00:04:04.910
Well the total cost would be
the sum of the implicit costs,

00:04:04.910 --> 00:04:07.880
which is opportunity cost
is an example of that,

00:04:07.880 --> 00:04:09.810
plus the explicit cost.

00:04:09.810 --> 00:04:12.120
So the implicit costs, we
already talked about that,

00:04:12.120 --> 00:04:13.293
that is $90.

00:04:14.190 --> 00:04:17.270
That's the cost of not,
that's the opportunity cost

00:04:17.270 --> 00:04:18.960
of not mowing lawns.

00:04:18.960 --> 00:04:22.400
And then to that you're
gonna add the explicit cost

00:04:22.400 --> 00:04:23.780
of just the price of the movie ticket.

00:04:23.780 --> 00:04:26.580
For $10 you get to watch
a movie for three hours.

00:04:26.580 --> 00:04:28.740
So there's a $10 explicit cost.

00:04:28.740 --> 00:04:32.880
So the total cost of going
to the movie is $100.

00:04:32.880 --> 00:04:35.610
And so how would an optimal decision

00:04:35.610 --> 00:04:38.250
or how would a rational
agent use this information

00:04:38.250 --> 00:04:40.130
to make an optimal decision?

00:04:40.130 --> 00:04:42.650
Well they would wanna
compare that to the benefit

00:04:42.650 --> 00:04:44.370
of going to a movie.

00:04:44.370 --> 00:04:46.740
And so if they could
quantify that benefit somehow

00:04:46.740 --> 00:04:50.080
and say oh, yeah, the benefit
to me of going to a movie

00:04:50.080 --> 00:04:54.430
is $200 and that difference
between $200 and $100,

00:04:54.430 --> 00:04:56.910
that's the best difference that I can get

00:04:56.910 --> 00:05:00.530
out of all of my choices between
my benefits and my costs.

00:05:00.530 --> 00:05:03.330
Well then I'm going to go to that movie.

00:05:03.330 --> 00:05:05.540
So I will leave you there
and in future videos,

00:05:05.540 --> 00:05:07.540
we'll dig a little bit deeper into this.