Comparative roles of women in Rome and Han China

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- [Sal] I'm here with Eman El-Sheikh,

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Khan Academy's World History Fellow.

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The question I have, Eman, is,

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history often focuses on men,

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but clearly, women were
playing a significant role,

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but how much can we know about
women, say, 2,000 years ago?

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- [Eman] So, when we talk about the lives

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of women in the Classical Period,

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sometimes we're tempted to
compare it to the modern day,

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and that can cause some problems

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because that's not
really a fair comparison.

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So it's more useful to
see how different women

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living in different societies

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in the same time period
compare to one another.

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That can make their
differences a lot more salient

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and give us a better idea.

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Of course, it's hard to know the history

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of women back then in general.

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We don't necessarily have
all the best sources.

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But we can try to piece
together some understanding

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of what their daily lives were like.

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- [Sal] We have two
points of reference here;

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one from Rome as it transitions
from republic to empire;

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and another from Han China.

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Let's look at the reference from Rome.

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Just for a little bit of context,

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this speech that we're gonna talk about,

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this occurs in 42 BCE.

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People might remember
that in 44 BCE you have

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Julius Caesar getting
assassinated on the Ides of March,

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and it throws the Roman
Empire into a civil war.

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And so, this speech is
given during that civil war.

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Because civil wars,
they're not just bloody,

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they're also expensive,
and to fund that civil war

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the triumvirs decide to tax
the 1400 wealthiest women.

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Hortensia, who gives this speech,

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is one of those wealthy women.

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- [Eman] Hortensia says:
"Why should we pay taxes

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"when we do not share
in the offices, honors,

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"military commands, nor,
in short, the government,

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"for which you fight between yourselves

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"with such harmful results?

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"You say 'because it is wartime.'

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"When has there not been war?

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"and when have women paid taxes?

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"By nature of their sex women are absolved

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"from paying taxes among all mankind.

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"Our mothers did once
rise superior to their sex

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"and made contributions
when you faced the loss

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"of the empire and the city itself

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"through the conflict
with the Carthaginians.

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"But they funded their
contributions voluntarily

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"from their jewelry not
from their landed property,

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"their fields, their
dowries, or their houses,

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"without which it is impossible
for free women to live...

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"Let war with the Celts or Parthians come,

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"we will not be inferior to our mothers

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"when it is a question of common safety.

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"But for civil wars,
may we never contribute

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"nor aid you against each other.

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"We did not pay taxes
to Caesar or to Pompey,

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"nor did Marius ask us for contributions,

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"nor Cinna, nor Sulla,

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"even though he was a
tyrant over this country.

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"And you say that you are
reestablishing the Republic!"

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- [Sal] Wow, that was quite powerful.

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And there's a lot of richness here.

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What's your takeaway?

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- [Eman] So, it's interesting
that she is saying that

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by nature of their sex women
are absolved from paying taxes.

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It might seem like she's
saying that women are weaker;

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but she's sort of speaking
back to this requirement

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that they should use their property.

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Because they're normally using
jewelry and they're normally

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using things that they
don't necessarily need

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in order to fight off foreigners.

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Here she's really taking issue with having

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to use her livelihood
to support a civil war,

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and she's sort of taking
them to task on this,

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that they're worse than
tyrants for asking this of her.

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- [Sal] The other thing
that jumps out of this,

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it comes outta the first few statements,

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"Why should we pay taxes
when we do not share

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"in the offices, honors,
military commands,

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"nor, in short, the government."

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She's making very clear, women
don't get to participate.

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Why should we fund this war?

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I also like this part.

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"You say 'because it is wartime.'

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"When has there not been war?"

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That's a really good point, because Rome,

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especially at that point,
was continuously conquering

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other peoples, continuously at war,

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sometimes a civil war,
sometimes an external war.

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- [Eman] Sure, and I
think it's interesting how

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she's pointing to that disparity between

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the things that men have
and women don't have.

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And she's just trying to say:
"Well, if that's how it's

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"going to be, then we should
also be exempt from taxation."

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I think that's an interesting
way to voice concerns.

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While this might seem very primitive

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to our modern sensibilities,

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it's really powerful that a woman

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is taking these government
officials to task

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and being so outspoken

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and quite scathing in
the way she does this.

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- [Sal] I also like the
second part right over here,

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where she is citing that our
mothers once also stepped up.

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She's referring to, during
the Second Punic War

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and Hannibal was running
amuck on the Italian Peninsula

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and even threatening Rome
itself, that the women of Rome,

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especially the wealthy women of Rome,

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did step up and pay taxes.

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- [Eman] So, based on this,
Sal, what do you think we can

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learn about Roman women and
their lives at this time period?

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- [Sal] Well, as we pointed
out, even in this speech

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she cites some direct reference

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to not having equality to men.

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But on the other hand,

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she has stormed the triumvirs' tribunal.

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I think this is the first
time that women were,

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they weren't even allowed
there, they just went there,

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and she's sticking it to the
triumvirs pretty strongly.

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She's saying: "Let war with
the Celts or Parthians come,

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"we will not be inferior to our mothers."

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"We're willing to step up if
it's war with external parties.

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"But for civil wars,
may we never contribute

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"nor aid you against each other."

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They're saying: "Hey, if
you wanna fight yourself,

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"that's your problem."

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And she's even telling 'em: "And you say

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"that you are reestablishing
the Republic!"

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She's questioning the three most

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powerful people in the Roman Empire.

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She's questioning their very intention.

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So it does show, at least culturally,

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even if officially women
do not have a strong role,

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at least these elite women
do have enough comfort

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to be able to go to
the three most powerful

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in the Roman Empire and stick it to them.

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- [Eman] Yeah, and while this
may not seem like a big deal

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to us now, we have to avoid
that comparison, like I said.

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If we compare it to some other societies

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around the same time,
this is quite remarkable

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for a woman to enter a public institution.

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Again, she is an elite woman,
but let's compare it to,

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say, Athenian women, even
elite woman in Athens,

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were not likely to have any involvement

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in the political institutions,

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were a lot more likely to just
remain in the private sphere,

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were not likely to be as
educated as Roman women.

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And so, the fact that
Hortensia can actually

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enter into the space and be so outspoken

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is sort of evidence of
the fact that Roman women

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had a degree more freedom than other women

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who were their contemporaries
in other societies.

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- [Sal] Absolutely.

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Let's continue that comparison.

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We can go about 100, 150 years further

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in the future from Hortensia's speech.

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Let's also go to the other side of,

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almost the other side of the world,

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we'll go to eastern Asia,

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where we are in the Eastern Han Dynasty.

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So here we have some text from Ban Zhao,

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who was a female historian,
astronomer, mathematician,

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Confucian, philosopher, coauthor of

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the official history book of Han.

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It's from her Lessons for Women.

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- [Eman] So, Ban Zhao says:

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"Let a woman modestly yield to others;

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"let her respect others;
let her put others first.

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"Herself, last."

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"Lay the (girl) baby
at birth below the bed

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"to plainly indicate that
she is lowly and weak,

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"and should regard it as her primary duty

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"to humble herself before others."

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"A husband can marry twice, but
his wife must never remarry.

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"Just as Heaven cannot be disobeyed,

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"so the wife cannot keep
away from her husband."

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"Man is honored for strength;

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"a woman is beautiful on
account of her gentleness."

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- [Sal] So what's your take on that?

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- [Eman] So, this is very much inline

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with the Confucian ideal of womanhood,

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and that's very much about a woman being

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very submissive to her male
relatives, and for her to stay

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very modest within the power
framework of her society,

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and to stay pretty much
within her own household,

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and to cultivate a life that
is meant to create comfort

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for the men in her
family and her children,

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and not much more than that.

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- [Sal] Yeah, I could not
imagine anyone who read this

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and took it seriously as
doing a lesson for themselves

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and storming the triumvirs' tribunals,

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even if they are an elite
woman in imperial China.

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- [Eman] Certainly, but I think
there's an important thing

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to remember, and that this
kind of document shows

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a prescriptive approach to women's lives.

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And that doesn't necessarily mean

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that women did live this way.

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The fact that Ban Zhao
herself is writing this

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is sort of ironic
because she's a woman who

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is putting herself out
there and writing things

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and not staying in the private sphere,

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so that's sort of a strange
contradiction there.

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But also, women who had a lot of wealth

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were likely to become educated like her.

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And also, it sort of
depended on their generation.

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Older women were likely
to have inheritances,

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property, just like
their Roman counterparts,

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and they were more likely
to engage in trade.

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We can find this out by
looking at other documents,

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like wills and so forth.

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So we can sort of see a tension between

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the prescriptive Confucian ideals

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and how women actually lived.

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In a lot of ways, having
wealth allowed women

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to buy their way out of these constrictive

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practices and ideas about women.

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- [Sal] I definitely
agree with that irony.

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It's quite thick here, because
she's telling other women

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to indicate that she is lowly and weak,

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but Ban Zhao herself, as I
mentioned, she's a historian,

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astronomer, mathematician,
Confucian, philosopher,

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she co-wrote one of the official histories

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of the Han empire, she's more
prominent and has done more

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than the great majority
of men in her time,

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so she's clearly not lowly and weak.

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So the irony is quite thick.

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- [Eman] Certainly.

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It's interesting to look
at these things because,

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like you said, it gives us
a sense of the difference.

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There seems to be quite
a different culture

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at play between Rome
and China at this time.

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And so, making that
kinda comparison gives us

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a lot more information about women's lives

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than simply saying that
there's a single history

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for all women of this time period,

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and that's simply not the case.

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As we can see, there are
huge differences between

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the civilizations; certainly,
even within civilizations

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there can be huge differences.

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- [Sal] Yes.

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Both of the examples we looked at

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have been very elite women.

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We're talking about women
well within the top 1%.

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If you went to more average women,

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their situation would
have been very different.

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- [Eman] Certainly.

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So, this idea that women
are supposed to have

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a nice home full of family
and stay within that,

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only wealthy women could
really live up to that;

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because if you have to leave
the house to make a living,

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you might not be able to
create this idyllic household

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full of children and spend
all your time managing that.

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So that's an important
difference, as well.

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- [Sal] Thanks, Eman.
This was really valuable.

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- [Eman] Thanks, Sal.


Hindu gods overview

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Language: en

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- [Instructor] Hinduism is often known

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for its large and
complex pantheon of gods.

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The goal of this video is
to give an overview of them

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and to think about how they are connected,

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and how they are perceived.

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So the Hindu Trinity,
as it is often called,

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is made up of Shiva, Vishnu and Brahma.

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They are often considered to be

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the three most important gods.

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In modern-day Hinduism,

00:00:25.992 --> 00:00:30.259
Shiva and Vishnu have
far more followership,

00:00:30.259 --> 00:00:31.534
I guess you can say,

00:00:31.534 --> 00:00:33.963
or more people view Shiva or Vishnu

00:00:33.963 --> 00:00:35.035
as the Supreme Being.

00:00:35.035 --> 00:00:37.851
There's more temples
dedicated to Shiva and Vishnu

00:00:37.851 --> 00:00:40.163
than there are too Brahma.

00:00:40.163 --> 00:00:41.783
Followers of Shiva,

00:00:41.783 --> 00:00:45.772
those who view him as the Supreme Being,

00:00:45.772 --> 00:00:47.385
they're called Shaivas.

00:00:47.385 --> 00:00:49.223
They're following Shaivism,

00:00:49.223 --> 00:00:52.268
or sometimes referred to as Shivaism.

00:00:52.268 --> 00:00:55.191
Shiva has multiple
aspects and as we'll see,

00:00:55.191 --> 00:00:57.992
many of these gods have multiple aspects

00:00:57.992 --> 00:00:59.698
and multiple connections,

00:00:59.698 --> 00:01:02.661
but is often referred to as the Destroyer

00:01:02.661 --> 00:01:04.932
or the Transformer.

00:01:04.932 --> 00:01:06.477
Vishnu, as I've mentioned,

00:01:06.477 --> 00:01:08.763
also has a significant following,

00:01:08.763 --> 00:01:12.042
a significant chunk of
Hindus are Vaishnivas,

00:01:12.042 --> 00:01:16.185
or followers of Vaishnavism or Vishnuism.

00:01:16.185 --> 00:01:19.357
And Vishnu is considered the Preserver.

00:01:19.357 --> 00:01:21.017
Brahma, as I mentioned,

00:01:21.017 --> 00:01:25.365
does not have as much followership
in modern-day Hinduism,

00:01:25.365 --> 00:01:28.248
but he is considered to be the Creator.

00:01:28.248 --> 00:01:30.023
Now in some narratives,

00:01:30.023 --> 00:01:32.786
he is the Creator and in other narratives,

00:01:32.786 --> 00:01:36.492
he has been created by
either Shiva or Vishnu.

00:01:36.492 --> 00:01:40.754
Now Brahma should not be
confused with Brahman,

00:01:40.754 --> 00:01:42.741
that we talked about in previous videos.

00:01:42.741 --> 00:01:46.552
Brahman is considered
the absolute reality.

00:01:46.552 --> 00:01:48.661
the true nature of things.

00:01:48.661 --> 00:01:52.282
And Brahma you could
view as an aspect of it.

00:01:52.282 --> 00:01:55.566
It is one God as part of
this true nature of things.

00:01:55.566 --> 00:01:57.479
In fact, everything you see on this video,

00:01:57.479 --> 00:01:59.096
in fact everything you see in reality,

00:01:59.096 --> 00:02:01.457
all of these gods to a Hindu

00:02:01.457 --> 00:02:05.284
could be considered as just
aspects of the true God

00:02:05.284 --> 00:02:07.867
or the true reality of Brahman.

00:02:08.725 --> 00:02:11.286
Now what's interesting in Hinduism

00:02:11.286 --> 00:02:15.453
is that gods are not viewed
to have a strict gender.

00:02:16.322 --> 00:02:19.989
For example, Vishnu has
a female incarnation

00:02:21.070 --> 00:02:23.874
and there's also groups of Hindus

00:02:23.874 --> 00:02:28.866
who view God as taking a
fundamentally female form.

00:02:28.866 --> 00:02:33.292
One group are known as
the followers of Shaktism.

00:02:33.292 --> 00:02:35.632
To Shaktism, God is female,

00:02:35.632 --> 00:02:38.747
the supreme goddess and takes many forms.

00:02:38.747 --> 00:02:40.531
Parvati as you see listed here

00:02:40.531 --> 00:02:42.346
is referred to the Divine Mother.

00:02:42.346 --> 00:02:46.041
She's viewed as Shiva's
consort or Shiva's wife,

00:02:46.041 --> 00:02:48.479
but she has other forms like Durga

00:02:48.479 --> 00:02:50.595
which is used as a stronger,

00:02:50.595 --> 00:02:52.568
more aggressive form of Parvati,

00:02:52.568 --> 00:02:54.905
sometimes referred to as Devi or Shakti.

00:02:54.905 --> 00:02:57.036
Shakti means strength or power

00:02:57.036 --> 00:02:59.012
and is a warrior goddess.

00:02:59.012 --> 00:03:01.787
You have Lakshmi who
is the wife of Vishnu,

00:03:01.787 --> 00:03:05.761
who represents or has aspects
of wealth and prosperity.

00:03:05.761 --> 00:03:08.021
You have Saraswati who has aspects

00:03:08.021 --> 00:03:10.168
of knowledge, music and the arts

00:03:10.168 --> 00:03:14.517
and is viewed as the consort
or the wife of Brahma.

00:03:14.517 --> 00:03:16.337
Now these are some of
the principal deities

00:03:16.337 --> 00:03:18.239
that we have on this top row,

00:03:18.239 --> 00:03:21.238
but there's also many, many
other significant deities.

00:03:21.238 --> 00:03:22.293
And as we will see,

00:03:22.293 --> 00:03:24.830
depending on what part of India you're in

00:03:24.830 --> 00:03:28.751
and which group subsect
of Hinduism you meet,

00:03:28.751 --> 00:03:31.277
they will place different
levels of emphasis

00:03:31.277 --> 00:03:32.502
on different deities

00:03:32.502 --> 00:03:35.085
and have different traditions
and different rituals.

00:03:35.085 --> 00:03:37.920
So Ganesh who is very recognizable

00:03:37.920 --> 00:03:40.198
because he has an elephant head,

00:03:40.198 --> 00:03:43.250
he is often referred to as Ganpati.

00:03:43.250 --> 00:03:46.955
He is viewed as the son
of Shiva and Parvati.

00:03:46.955 --> 00:03:49.659
There's a great story about how he,

00:03:49.659 --> 00:03:52.262
why he has this elephant head.

00:03:52.262 --> 00:03:55.265
He is viewed as the god of new beginnings

00:03:55.265 --> 00:03:57.662
and the remover of obstacles.

00:03:57.662 --> 00:04:00.549
He has a lot of followership
and he is revered

00:04:00.549 --> 00:04:02.665
in a lot of regions of western India,

00:04:02.665 --> 00:04:03.799
and that's not the only places,

00:04:03.799 --> 00:04:06.712
but he is known to be a principal God

00:04:06.712 --> 00:04:08.150
in some of these regions.

00:04:08.150 --> 00:04:10.581
Durga similarly, that I referred to,

00:04:10.581 --> 00:04:12.770
in eastern India, especially Bengal,

00:04:12.770 --> 00:04:14.559
the place where my family comes from,

00:04:14.559 --> 00:04:17.117
Durga Puja, the Puja for Durga,

00:04:17.117 --> 00:04:20.120
the rituals for Durga are considered to be

00:04:20.120 --> 00:04:24.037
a very the important part
of the Hindu religion.

00:04:24.037 --> 00:04:25.762
If you go into the south,

00:04:25.762 --> 00:04:27.245
for some Hindus,

00:04:27.245 --> 00:04:30.138
Karthikeya or also known as Murugan,

00:04:30.138 --> 00:04:32.268
might be a significant deity.

00:04:32.268 --> 00:04:34.520
That is the god of war.

00:04:34.520 --> 00:04:37.702
Vishnu is known to have
multiple incarnations

00:04:37.702 --> 00:04:39.246
that are very prominent.

00:04:39.246 --> 00:04:42.123
The most prominent of which are Rama,

00:04:42.123 --> 00:04:43.992
Vishnu's seventh incarnation.

00:04:43.992 --> 00:04:46.723
He is the main protagonist in the Ramayan,

00:04:46.723 --> 00:04:48.582
the famous Hindu epic.

00:04:48.582 --> 00:04:52.258
You have Krishna, who is
Vishnu's eighth incarnation.

00:04:52.258 --> 00:04:54.672
And he is a significant
figure throughout Hinduism,

00:04:54.672 --> 00:04:56.278
including the Mahabharata

00:04:56.278 --> 00:04:58.142
and the subset of the Mahabharata,

00:04:58.142 --> 00:05:00.465
which is the Bhagavad Gita.

00:05:00.465 --> 00:05:01.781
Now what's really interesting,

00:05:01.781 --> 00:05:03.329
and I already alluded to it,

00:05:03.329 --> 00:05:07.591
is you have all of this
diversity in Hinduism.

00:05:07.591 --> 00:05:10.351
Someone who worships Shiva,

00:05:10.351 --> 00:05:12.678
you might see at a superficial level,

00:05:12.678 --> 00:05:15.830
seems more different in their
rituals and their beliefs

00:05:15.830 --> 00:05:18.591
from someone who worships Vishnu,

00:05:18.591 --> 00:05:21.842
than say, a Protestant from
a Catholic in Christianity

00:05:21.842 --> 00:05:24.509
or a Sunni from a Shia in Islam.

00:05:25.779 --> 00:05:27.971
And what's fascinating about Hinduism

00:05:27.971 --> 00:05:30.323
is that you don't see
these traditional schisms,

00:05:30.323 --> 00:05:32.314
you don't see a lot of conflict

00:05:32.314 --> 00:05:35.287
between the Shaivas or the Vaishnavas,

00:05:35.287 --> 00:05:36.462
because to Hindus,

00:05:36.462 --> 00:05:38.656
even though you have this
diversity of practice

00:05:38.656 --> 00:05:41.785
across India or across
the Hindu tradition,

00:05:41.785 --> 00:05:45.849
they're all viewed as aspects of Brahman.

00:05:45.849 --> 00:05:49.793
They're all viewed as
different ways to visualize

00:05:49.793 --> 00:05:53.241
or to connect with the fundamental reality

00:05:53.241 --> 00:05:55.355
or the fundamental god.

00:05:55.355 --> 00:05:58.688
And because Hinduism
has been able to merge

00:05:58.688 --> 00:06:00.514
these very diverse practices,

00:06:00.514 --> 00:06:01.814
these very diverse rituals,

00:06:01.814 --> 00:06:05.541
and it's believed this emerged
because as Hinduism emerged,

00:06:05.541 --> 00:06:08.520
it took traditions from the
Indus valley civilization.

00:06:08.520 --> 00:06:11.359
It took significant traditions
from the Indo-Aryans.

00:06:11.359 --> 00:06:14.234
It took significant traditions
from the Dravidians.

00:06:14.234 --> 00:06:16.021
Instead of saying, "Hey
our different traditions

00:06:16.021 --> 00:06:17.494
"are different religions,"

00:06:17.494 --> 00:06:21.167
they merged over thousands
of years into one religion.

00:06:21.167 --> 00:06:22.960
And the word for this merging,

00:06:22.960 --> 00:06:25.727
taking an amalgamation
of multiple rituals,

00:06:25.727 --> 00:06:28.962
multiple ideas, multiple,
multiple practices,

00:06:28.962 --> 00:06:30.775
and turning them into one

00:06:30.775 --> 00:06:33.302
is known as syncretism.

00:06:33.302 --> 00:06:37.537
Hinduism is perhaps the
best example of syncretism

00:06:37.537 --> 00:06:40.527
where you have these
incredibly diverse practices.

00:06:40.527 --> 00:06:43.572
The gods that I show here
are just a sample of them,

00:06:43.572 --> 00:06:46.010
but they've been connected
through this overarching,

00:06:46.010 --> 00:06:49.266
very diverse religion called Hinduism.

00:06:49.266 --> 00:06:50.321
And to a Hindu,

00:06:50.321 --> 00:06:55.239
they're all ways of connecting
with the fundamental Brahman.

00:06:55.239 --> 00:06:57.356
And to remind that,

00:06:57.356 --> 00:06:59.548
we could just zoom out

00:06:59.548 --> 00:07:02.715
and we see the connection with Brahman

00:07:03.810 --> 00:07:06.751
which is viewed as this
fundamental reality.

00:07:06.751 --> 00:07:09.016
Which raises an interesting question.

00:07:09.016 --> 00:07:12.548
Hinduism is oftentimes cited
as a polytheistic religion.

00:07:12.548 --> 00:07:14.488
Polytheism, you have multiple gods.

00:07:14.488 --> 00:07:17.487
And clearly, I've cited multiple
gods even in this video,

00:07:17.487 --> 00:07:21.053
and this is a sample of all
of the gods in Hinduism.

00:07:21.053 --> 00:07:22.353
But at the same time,

00:07:22.353 --> 00:07:25.225
they're all perceived
by many or most Hindus

00:07:25.225 --> 00:07:27.722
as to being aspects or ways to connect

00:07:27.722 --> 00:07:30.640
with the fundamental reality of Brahman

00:07:30.640 --> 00:07:35.064
who many Hindus would call to
be the true fundamental God.

00:07:35.064 --> 00:07:36.410
And so based on that they would say,

00:07:36.410 --> 00:07:38.864
"These are just aspects of the one God."

00:07:38.864 --> 00:07:41.945
And so they would argue
that it is monotheistic.

00:07:41.945 --> 00:07:44.869
So I'll let you decide how you view it

00:07:44.869 --> 00:07:47.743
or if it even matters to put apply a label

00:07:47.743 --> 00:07:50.678
like monotheism or polytheism

00:07:50.678 --> 00:07:52.877
to the idea of Hinduism.

00:07:52.877 --> 00:07:54.665
The big picture is,

00:07:54.665 --> 00:07:57.492
is that you have many
gods and many practices

00:07:57.492 --> 00:08:01.283
and they are diverse
across the Hindu world,

00:08:01.283 --> 00:08:03.770
but they are all viewed as connected

00:08:03.770 --> 00:08:06.187
to this notion of a Brahman.


Electron affinity: period trend

WEBVTT
Kind: captions
Language: en

00:00:01.997 --> 00:00:04.305
- [Instructor] Before we
get into electron affinity,

00:00:04.305 --> 00:00:07.390
let's really quickly
review ionization energy.

00:00:07.390 --> 00:00:10.188
And let's start with a
neutral lithium atom,

00:00:10.188 --> 00:00:13.978
with an electron configuration
of one s two, two s one.

00:00:13.978 --> 00:00:16.934
A lithium atom has three
protons in the nucleus,

00:00:16.934 --> 00:00:18.898
so a positive three charge.

00:00:18.898 --> 00:00:21.228
Two electrons in the one s orbital,

00:00:21.228 --> 00:00:24.154
so here are the two electrons
in the one s orbital,

00:00:24.154 --> 00:00:26.039
or our core electrons,

00:00:26.039 --> 00:00:28.646
and one electron in a two s orbital.

00:00:28.646 --> 00:00:32.339
This is our outermost
electron, our valence electron.

00:00:32.339 --> 00:00:35.076
The valence electron is shielded

00:00:35.076 --> 00:00:37.473
from the full positive
three charge of the nucleus

00:00:37.473 --> 00:00:40.153
by the presence of the core electrons.

00:00:40.153 --> 00:00:41.820
So like charges repel,

00:00:41.820 --> 00:00:45.107
and these core electrons
repel this outer electron,

00:00:45.107 --> 00:00:48.346
and shield it from the
full positive three charge.

00:00:48.346 --> 00:00:50.474
But there still is an attractive force

00:00:50.474 --> 00:00:52.438
between the positively charged nucleus

00:00:52.438 --> 00:00:54.708
and this outermost electron.

00:00:54.708 --> 00:00:58.612
So opposite charges attract,
and our outermost electron

00:00:58.612 --> 00:01:01.719
still feels a pull from the nucleus.

00:01:01.719 --> 00:01:04.318
Therefore, since the outer
electron is attracted

00:01:04.318 --> 00:01:06.523
to the nucleus, it takes energy

00:01:06.523 --> 00:01:08.940
to completely pull away
this valence electron

00:01:08.940 --> 00:01:10.835
from the neutral atom.

00:01:10.835 --> 00:01:13.285
So if we pull away the outermost electron,

00:01:13.285 --> 00:01:15.697
we lose our valence electron,

00:01:15.697 --> 00:01:19.066
and we're left with a lithium
ion, with a positive charge.

00:01:19.066 --> 00:01:22.255
Positive one charge, because
we still have three protons,

00:01:22.255 --> 00:01:24.507
but only two electrons now,

00:01:24.507 --> 00:01:26.570
so overall a plus one charge.

00:01:26.570 --> 00:01:30.987
Since this ionization takes
energy to rip away the electron,

00:01:30.987 --> 00:01:34.059
the energy, the ionization
energy, is positive,

00:01:34.059 --> 00:01:36.706
and is measured in kiloJoules per mol.

00:01:36.706 --> 00:01:39.656
Let's compare that with electron affinity.

00:01:39.656 --> 00:01:42.117
So, in electron affinity,
let's say we're starting

00:01:42.117 --> 00:01:44.968
with our neutral lithium atom again,

00:01:44.968 --> 00:01:47.891
but this time, instead of
taking an electron away,

00:01:47.891 --> 00:01:50.183
we are adding an electron.

00:01:50.183 --> 00:01:54.029
So, we would add an electron
to the two s orbital.

00:01:54.029 --> 00:01:55.883
So we started off with three electrons

00:01:55.883 --> 00:01:59.440
in the neutral lithium atom,
and we're adding one more.

00:01:59.440 --> 00:02:02.837
So the electron configuration
for the lithium ion

00:02:02.837 --> 00:02:06.015
would be one s two, two s two.

00:02:06.015 --> 00:02:09.339
So still three positive
charges in the nucleus,

00:02:09.339 --> 00:02:12.001
two electrons in the one s orbital,

00:02:12.001 --> 00:02:13.914
but now we've added an electron,

00:02:13.914 --> 00:02:16.138
so we have four electrons total,

00:02:16.138 --> 00:02:18.221
two in the two s orbital.

00:02:19.163 --> 00:02:22.903
So let me highlight the electron
that we added in magenta.

00:02:22.903 --> 00:02:24.859
So this is the electron that we added

00:02:24.859 --> 00:02:27.619
to a neutral lithium atom.

00:02:27.619 --> 00:02:30.117
And this electron, we know, is shielded

00:02:30.117 --> 00:02:32.880
from the full positive
three charge of the nucleus

00:02:32.880 --> 00:02:35.833
by our two core electrons in here, right?

00:02:35.833 --> 00:02:37.373
So like charges repel.

00:02:37.373 --> 00:02:39.489
It's also going to be
repelled a little bit

00:02:39.489 --> 00:02:43.908
by this electron, that's
also in the two s orbital.

00:02:43.908 --> 00:02:47.064
So this electron's going
to repel this one as well.

00:02:47.064 --> 00:02:49.331
But, there is an attractive force

00:02:49.331 --> 00:02:51.710
between our positively charged nucleus

00:02:51.710 --> 00:02:55.166
and our negative charge on the electron.

00:02:55.166 --> 00:02:57.138
So this electron that we added

00:02:57.138 --> 00:03:00.875
still feels an attractive
force that's pulling on it

00:03:00.875 --> 00:03:02.292
from the nucleus.

00:03:03.310 --> 00:03:06.044
And so, if you add this fourth electron,

00:03:06.044 --> 00:03:07.711
energy is given off.

00:03:08.755 --> 00:03:11.635
And since energy is given
off, this is going to have

00:03:11.635 --> 00:03:14.654
a negative value for
the electron affinity.

00:03:14.654 --> 00:03:17.802
For adding an electron to
a neutral lithium atom,

00:03:17.802 --> 00:03:21.302
it turns out to be -60 kiloJoules per mol.

00:03:22.531 --> 00:03:26.596
So energy is released
when an electron is added,

00:03:26.596 --> 00:03:29.121
and that is because the
electron that we added

00:03:29.121 --> 00:03:33.189
is still able to be attracted
to the charged nucleus.

00:03:33.189 --> 00:03:36.923
So if the nucleus has an
attraction for the added electron,

00:03:36.923 --> 00:03:38.589
you're going to get a negative value

00:03:38.589 --> 00:03:40.733
for the electron affinity.

00:03:40.733 --> 00:03:43.905
Or that's one way to
measure electron affinity.

00:03:43.905 --> 00:03:46.665
Note that the lithium anion is larger

00:03:46.665 --> 00:03:48.489
than the neutral lithium atom.

00:03:48.489 --> 00:03:51.476
It's just hard to represent
it here with those diagrams.

00:03:51.476 --> 00:03:53.298
So as long as the added electron

00:03:53.298 --> 00:03:55.980
feels an attractive
force from the nucleus,

00:03:55.980 --> 00:03:57.647
energy is given off.

00:03:58.750 --> 00:04:00.066
Let's look at one more comparison

00:04:00.066 --> 00:04:03.003
between ionization energy
and electron affinity.

00:04:03.003 --> 00:04:06.683
In ionization energy, since
the outer electron here

00:04:06.683 --> 00:04:10.909
is attracted to the nucleus,
we have to work hard

00:04:10.909 --> 00:04:12.886
to pull that electron away.

00:04:12.886 --> 00:04:15.802
It takes energy for us to
rip away that electron.

00:04:15.802 --> 00:04:18.047
And since it takes us
energy, we have to do work,

00:04:18.047 --> 00:04:22.495
and the energy is positive,
in terms of ionization energy.

00:04:22.495 --> 00:04:25.078
But for electron affinity,
since the electron

00:04:25.078 --> 00:04:26.817
that we're adding is attracted

00:04:26.817 --> 00:04:28.854
to the positive charge of the nucleus,

00:04:28.854 --> 00:04:30.303
we don't have to force this,

00:04:30.303 --> 00:04:31.729
we don't have to do any work.

00:04:31.729 --> 00:04:34.450
Energy is given off in this
process, and that's why

00:04:34.450 --> 00:04:38.527
it's a negative value for
the electron affinity.

00:04:38.527 --> 00:04:41.041
Electron affinities don't
have to be negative.

00:04:41.041 --> 00:04:43.181
For some atoms, there's
actually no attraction

00:04:43.181 --> 00:04:45.294
for an extra electron.

00:04:45.294 --> 00:04:47.279
Let's take neon, for example.

00:04:47.279 --> 00:04:49.283
Neon has an electron configuration

00:04:49.283 --> 00:04:52.533
of one s two, two s two, and two p six.

00:04:54.353 --> 00:04:57.107
So there's a total of
two plus two plus six,

00:04:57.107 --> 00:05:00.934
or 10 electrons, and a positive
10 charge in the nucleus

00:05:00.934 --> 00:05:03.188
for a neutral neon atom.

00:05:03.188 --> 00:05:05.351
So let's say this is our nucleus here,

00:05:05.351 --> 00:05:07.618
with a positive 10 charge, 10 protons.

00:05:07.618 --> 00:05:10.753
And then we have our 10 electrons here,

00:05:10.753 --> 00:05:12.753
surrounding our nucleus.

00:05:13.650 --> 00:05:16.154
So this is our neutral neon atom.

00:05:16.154 --> 00:05:18.352
If we try to add an electron,

00:05:18.352 --> 00:05:20.413
so here let's add an electron.

00:05:20.413 --> 00:05:23.277
So we still have our 10
protons in the nucleus.

00:05:23.277 --> 00:05:25.383
We still have our 10 electrons,

00:05:25.383 --> 00:05:27.704
which would now be our core electrons.

00:05:27.704 --> 00:05:32.574
To add a new electron, this
would be the neon anion here,

00:05:32.574 --> 00:05:35.491
so one s two, two s two, two p six.

00:05:36.638 --> 00:05:38.597
We've filled the second energy level.

00:05:38.597 --> 00:05:42.841
To add an electron, we must
go to a new energy level.

00:05:42.841 --> 00:05:44.793
So it would be the third energy level,

00:05:44.793 --> 00:05:46.122
it would be an s orbital,

00:05:46.122 --> 00:05:48.796
and there would be one
electron in that orbital.

00:05:48.796 --> 00:05:51.596
So, here is, let's say
this is the electron

00:05:51.596 --> 00:05:52.953
that we just added.

00:05:52.953 --> 00:05:57.372
So we have to try to add an
electron to our neon atom.

00:05:57.372 --> 00:06:01.124
But if you think about the
effective nuclear charge

00:06:01.124 --> 00:06:04.108
that this electron in magenta feels,

00:06:04.108 --> 00:06:06.631
alright, so the effective nuclear charge,

00:06:06.631 --> 00:06:09.849
that's equal to the atomic
number, or the number of protons,

00:06:09.849 --> 00:06:11.173
and from that, you subtract

00:06:11.173 --> 00:06:13.454
the number of shielding electrons.

00:06:13.454 --> 00:06:17.490
Since we have 10 protons in
the nucleus, this would be 10.

00:06:17.490 --> 00:06:20.674
And our shielding electrons
would be 10, as well.

00:06:20.674 --> 00:06:23.695
So those 10 electrons
shield this added electron

00:06:23.695 --> 00:06:27.695
from the full positive
10 charge of the nucleus.

00:06:28.746 --> 00:06:30.960
And for a quick calculation, this tells us

00:06:30.960 --> 00:06:34.558
that the effective nuclear charge is zero.

00:06:34.558 --> 00:06:36.183
And this is, you know, simplifying things

00:06:36.183 --> 00:06:37.911
a little bit, but you can think

00:06:37.911 --> 00:06:40.660
about this outer electron
that we tried to add,

00:06:40.660 --> 00:06:43.644
of not having any
attraction for the nucleus.

00:06:43.644 --> 00:06:45.734
These 10 electrons shield it completely

00:06:45.734 --> 00:06:47.716
from the positive 10 charge.

00:06:47.716 --> 00:06:50.778
And since there's no
attraction for this electron,

00:06:50.778 --> 00:06:53.244
energy is not given off in this process.

00:06:53.244 --> 00:06:55.136
Actually, it would take energy

00:06:55.136 --> 00:06:58.165
to force an electron onto neon.

00:06:58.165 --> 00:07:00.114
So if you wrote something out here,

00:07:00.114 --> 00:07:02.352
and if we said, alright,
I'm trying to go from,

00:07:02.352 --> 00:07:04.363
I'm trying to add an electron to neon,

00:07:04.363 --> 00:07:06.866
to turn it into an anion.

00:07:06.866 --> 00:07:08.324
Instead of giving off energy,

00:07:08.324 --> 00:07:10.783
this process would take energy.

00:07:10.783 --> 00:07:12.240
So we would have to force,

00:07:12.240 --> 00:07:15.033
we would have to try
to force this to occur.

00:07:15.033 --> 00:07:17.420
So it takes energy to force an electron

00:07:17.420 --> 00:07:19.651
on a neutral atom of neon.

00:07:19.651 --> 00:07:23.818
And we say that neon has no
affinity for an electron.

00:07:24.662 --> 00:07:28.062
So it's unreactive, it's a
noble gas, and this is one way

00:07:28.062 --> 00:07:31.757
to explain why noble gases are unreactive.

00:07:31.757 --> 00:07:33.677
This anion that we intended

00:07:33.677 --> 00:07:35.631
isn't going to stay around for long.

00:07:35.631 --> 00:07:39.681
So it takes energy to force
this onto our neutral neon atom.

00:07:39.681 --> 00:07:41.868
So you could say that
the electron affinity

00:07:41.868 --> 00:07:44.223
is positive here, it takes energy.

00:07:44.223 --> 00:07:46.815
But usually, you don't see positive values

00:07:46.815 --> 00:07:49.785
for electron affinity, for
this sort of situation.

00:07:49.785 --> 00:07:51.931
At least, most textbooks
I've looked at would just say

00:07:51.931 --> 00:07:54.652
the electron affinity of neon is zero,

00:07:54.652 --> 00:07:57.230
since I believe it is hard to measure

00:07:57.230 --> 00:07:59.430
the actual value of this.

00:07:59.430 --> 00:08:01.288
Here we have the elements
in the second period

00:08:01.288 --> 00:08:02.850
on the periodic table, and let's look

00:08:02.850 --> 00:08:04.845
at their electron affinities.

00:08:04.845 --> 00:08:06.816
We've already seen that adding an electron

00:08:06.816 --> 00:08:08.920
to a neutral atom of lithium

00:08:08.920 --> 00:08:12.107
gives off 60 kiloJoules per mol.

00:08:12.107 --> 00:08:14.953
Next, we have beryllium, with a zero value

00:08:14.953 --> 00:08:16.750
for the electron affinity.

00:08:16.750 --> 00:08:18.651
That means it actually takes energy.

00:08:18.651 --> 00:08:20.344
So this number is actually positive,

00:08:20.344 --> 00:08:23.291
and it takes energy to add an electron

00:08:23.291 --> 00:08:25.725
to a neutral atom of beryllium.

00:08:25.725 --> 00:08:28.532
So if you think about going
from a neutral atom of beryllium

00:08:28.532 --> 00:08:30.797
to form the beryllium anion,

00:08:30.797 --> 00:08:33.185
when we look at electron configurations,

00:08:33.185 --> 00:08:36.594
neutral atom of beryllium
is one s two, two s two,

00:08:36.594 --> 00:08:39.971
and so, to form the negatively
charged beryllium anion,

00:08:39.971 --> 00:08:42.515
it would be one s two, two s two,

00:08:42.515 --> 00:08:45.702
and to add the extra electron, it must go

00:08:45.702 --> 00:08:49.702
into a two p orbital,
which is of higher energy.

00:08:50.616 --> 00:08:53.713
And so, this is actually the
same thing, or very similar,

00:08:53.713 --> 00:08:56.646
to neon, which we just discussed.

00:08:56.646 --> 00:08:59.609
For neon, the electron
configuration was one s two,

00:08:59.609 --> 00:09:04.155
two s two, two p six, and
to add an extra electron,

00:09:04.155 --> 00:09:06.521
we had to go to the third energy level.

00:09:06.521 --> 00:09:08.575
We had to open up a new shell.

00:09:08.575 --> 00:09:11.346
And the electron that we
added was effectively screened

00:09:11.346 --> 00:09:15.404
from the full nuclear charge
by these other electrons.

00:09:15.404 --> 00:09:18.512
And a similar thing happens
here for the beryllium anion.

00:09:18.512 --> 00:09:21.320
To add this extra electron,
we have to open up

00:09:21.320 --> 00:09:23.492
a higher energy p orbital.

00:09:23.492 --> 00:09:26.702
This electron is, on average,
further away from the nucleus,

00:09:26.702 --> 00:09:29.217
and is effectively shielded
from the full positive

00:09:29.217 --> 00:09:33.142
charge of the nucleus, and
therefore, there's no affinity

00:09:33.142 --> 00:09:35.365
for this added electron.

00:09:35.365 --> 00:09:37.424
So there's no affinity for this electron,

00:09:37.424 --> 00:09:41.347
so it takes energy to
form the beryllium anion.

00:09:41.347 --> 00:09:44.823
And that's why we see this
zero value here for beryllium.

00:09:44.823 --> 00:09:47.405
Beryllium has no value
for electron affinity,

00:09:47.405 --> 00:09:49.663
or, it's actually a very positive value,

00:09:49.663 --> 00:09:51.868
and we just say it has a zero value.

00:09:51.868 --> 00:09:53.612
Next, let's look at boron here.

00:09:53.612 --> 00:09:56.836
So this gives off -27 kiloJoules per mol.

00:09:56.836 --> 00:09:59.434
And we can see a little
bit of a trend here,

00:09:59.434 --> 00:10:03.601
as we go from boron to
carbon to oxygen to fluorine.

00:10:04.620 --> 00:10:08.787
So as we go across the
period on the periodic table,

00:10:10.117 --> 00:10:13.969
more energy is given off, and therefore,

00:10:13.969 --> 00:10:17.959
fluorine has the most
affinity for an electron.

00:10:17.959 --> 00:10:20.444
So as we go across a
period, we get an increase

00:10:20.444 --> 00:10:22.462
in the electron affinity.

00:10:22.462 --> 00:10:25.392
So the negative sign just
means that energy is given off,

00:10:25.392 --> 00:10:27.630
so we're really just
looking at the magnitude.

00:10:27.630 --> 00:10:29.694
More energy is given off when you add

00:10:29.694 --> 00:10:32.925
an electron to a neutral atom of fluorine,

00:10:32.925 --> 00:10:37.111
than if you add an electron
to a neutral atom of oxygen.

00:10:37.111 --> 00:10:39.000
And we can explain this general trend

00:10:39.000 --> 00:10:41.933
in terms of effective nuclear charge.

00:10:41.933 --> 00:10:45.665
As we go across our period,
we also have an increase

00:10:45.665 --> 00:10:48.931
in the effective nuclear charge.

00:10:48.931 --> 00:10:51.644
And if the added electron
is feeling more of a pull

00:10:51.644 --> 00:10:54.375
from the nucleus, which
is what we mean here

00:10:54.375 --> 00:10:57.589
by increased effective nuclear charge,

00:10:57.589 --> 00:11:01.820
more energy will be given off
when we add that electron.

00:11:01.820 --> 00:11:04.962
So this idea explains the general trend

00:11:04.962 --> 00:11:08.606
we see for electron affinity,
as you go across a period,

00:11:08.606 --> 00:11:11.626
we get an increase in
the electron affinity.

00:11:11.626 --> 00:11:14.912
We've already talked about
beryllium as an exception,

00:11:14.912 --> 00:11:18.867
neon as an exception, but
what about nitrogen in here?

00:11:18.867 --> 00:11:21.009
We can see that nitrogen
doesn't really have

00:11:21.009 --> 00:11:24.016
an affinity for an
electron, and you'll see

00:11:24.016 --> 00:11:25.853
many different values for this one,

00:11:25.853 --> 00:11:28.047
depending on which
textbook you're looking in.

00:11:28.047 --> 00:11:30.230
But if we look at some
electron configurations

00:11:30.230 --> 00:11:33.322
really quickly, we can
try to explain this.

00:11:33.322 --> 00:11:37.001
So, for nitrogen, the
electron configuration

00:11:37.001 --> 00:11:40.834
is one s two, two s two,
and then two p three.

00:11:42.287 --> 00:11:44.371
So if we draw out our orbitals,

00:11:44.371 --> 00:11:46.548
let's just say this is the two s orbital,

00:11:46.548 --> 00:11:49.350
and then these are the
three two p orbitals.

00:11:49.350 --> 00:11:51.262
So we'll just do these electrons here.

00:11:51.262 --> 00:11:53.429
Two electrons in the two s orbital,

00:11:53.429 --> 00:11:56.692
and then we have three
electrons in the p orbital.

00:11:56.692 --> 00:11:58.353
So let's draw those in there.

00:11:58.353 --> 00:12:02.778
If we try to add an electron
to a neutral nitrogen atom,

00:12:02.778 --> 00:12:05.479
we're adding an electron
to one of these orbitals,

00:12:05.479 --> 00:12:08.019
which already has an electron in it.

00:12:08.019 --> 00:12:12.049
So adding an electron to one
of these orbitals, right,

00:12:12.049 --> 00:12:14.221
the added electron would be repelled

00:12:14.221 --> 00:12:16.895
by the electron that was
in there to start with.

00:12:16.895 --> 00:12:19.521
And this is the reason that
you usually see in textbooks

00:12:19.521 --> 00:12:22.054
for the fact that this
does not follow the trend.

00:12:22.054 --> 00:12:26.221
Nitrogen doesn't have an
affinity for one added electron.

00:12:27.283 --> 00:12:28.942
So after going through all of that,

00:12:28.942 --> 00:12:30.766
it's obvious that electron affinity

00:12:30.766 --> 00:12:34.062
is a little more complicated
than ionization energy.

00:12:34.062 --> 00:12:36.692
In ionization energy, we
had a pretty clear trend,

00:12:36.692 --> 00:12:39.274
and it was a little easier to explain why.

00:12:39.274 --> 00:12:42.297
For electron affinity,
going across a period

00:12:42.297 --> 00:12:45.631
on the periodic table, we
see a little bit of a trend,

00:12:45.631 --> 00:12:47.572
but there are many exceptions to this,

00:12:47.572 --> 00:12:51.381
and perhaps our explanations
are a little bit too simplistic

00:12:51.381 --> 00:12:54.234
to explain actually what's going on.

00:12:54.234 --> 00:12:57.465
But across a period, you do
see a little bit of a trend.

00:12:57.465 --> 00:12:59.502
Going down a group is much harder.

00:12:59.502 --> 00:13:02.650
You see more inconsistencies,
and it's not really even worth

00:13:02.650 --> 00:13:05.109
going over a general trend for that.


Ionization energy: period trend

WEBVTT
Kind: captions
Language: en

00:00:01.863 --> 00:00:03.319
- [Instructor] In this
video, let's look at

00:00:03.319 --> 00:00:06.630
the periodic trends for ionization energy.

00:00:06.630 --> 00:00:07.723
So, for this period,

00:00:07.723 --> 00:00:09.524
as we go across from lithium,

00:00:09.524 --> 00:00:11.668
all the way over to neon,

00:00:11.668 --> 00:00:15.877
so as we go this way,
across our periodic table,

00:00:15.877 --> 00:00:18.158
we can see, in general,
there's an increase

00:00:18.158 --> 00:00:20.384
in the ionization energy.

00:00:20.384 --> 00:00:24.375
So, lithium is positive
520 kilojoules per mole.

00:00:24.375 --> 00:00:27.841
Beryllium's goes up to
900 kilojoules per mole,

00:00:27.841 --> 00:00:30.628
and then again, in general,
we see this increase

00:00:30.628 --> 00:00:34.542
in ionization energies going over to neon.

00:00:34.542 --> 00:00:35.866
So, going across a period,

00:00:35.866 --> 00:00:39.427
there's an increase in
the ionization energy.

00:00:39.427 --> 00:00:40.647
And that's because,

00:00:40.647 --> 00:00:42.259
as we go across our period,

00:00:42.259 --> 00:00:46.455
there's an increase in the
effective nuclear charge.

00:00:46.455 --> 00:00:48.474
So, increase in Z effective.

00:00:48.474 --> 00:00:50.963
And remember, the formula for that is

00:00:50.963 --> 00:00:54.094
the effective nuclear charge is equal to

00:00:54.094 --> 00:00:56.923
the actual number of protons, which is Z,

00:00:56.923 --> 00:00:58.975
and from that we subtract S,

00:00:58.975 --> 00:01:01.600
which is the average
number of inner electrons

00:01:01.600 --> 00:01:04.195
shielding our outer electrons.

00:01:04.195 --> 00:01:06.698
So, let's examine this in more detail,

00:01:06.698 --> 00:01:09.756
looking at lithium and beryllium.

00:01:09.756 --> 00:01:11.732
Lithium has atomic number three,

00:01:11.732 --> 00:01:13.992
so three protons in the nucleus,

00:01:13.992 --> 00:01:16.389
so positive three charge,

00:01:16.389 --> 00:01:19.134
and lithium's electron
configuration we know

00:01:19.134 --> 00:01:21.134
is one s two, two s one.

00:01:22.192 --> 00:01:25.012
So, two electrons in our one s orbital,

00:01:25.012 --> 00:01:28.878
and one electron in the two s orbital.

00:01:28.878 --> 00:01:31.337
Beryllium has one more proton

00:01:31.337 --> 00:01:32.925
and one more electron.

00:01:32.925 --> 00:01:37.192
So one more proton in the
nucleus, so a plus 4 charge,

00:01:37.192 --> 00:01:40.528
and for beryllium, the
electron configuration is

00:01:40.528 --> 00:01:42.702
one s two, two s two.

00:01:42.702 --> 00:01:45.285
So two electrons in the one s orbital,

00:01:45.285 --> 00:01:49.650
and then two electrons
in the two s orbital.

00:01:49.650 --> 00:01:52.321
Let's calculate the
effective nuclear charge

00:01:52.321 --> 00:01:54.065
for both of these,

00:01:54.065 --> 00:01:56.570
and first, we'll start with lithium.

00:01:56.570 --> 00:01:58.183
So for lithium,

00:01:58.183 --> 00:02:01.741
lithium has a plus three
charge in the nucleus,

00:02:01.741 --> 00:02:05.880
so the effective nuclear charge
is equal to positive three,

00:02:05.880 --> 00:02:09.987
and from that we subtract
the average number of inner

00:02:09.987 --> 00:02:12.558
electrons shielding our outer electrons,

00:02:12.558 --> 00:02:14.583
in this case, we have these two inner,

00:02:14.583 --> 00:02:18.517
or core electrons, that are
shielding our outer electron,

00:02:18.517 --> 00:02:22.328
our valence electron, from this
full positive three charge.

00:02:22.328 --> 00:02:24.855
So we know that like charges repel,

00:02:24.855 --> 00:02:26.475
so this electron is going to repel

00:02:26.475 --> 00:02:28.600
this electron a little bit,

00:02:28.600 --> 00:02:31.368
and this electron repels this electron.

00:02:31.368 --> 00:02:34.523
And these two inner core
electrons of lithium

00:02:34.523 --> 00:02:35.947
have a shielding effect,

00:02:35.947 --> 00:02:37.335
they protect the outer electron

00:02:37.335 --> 00:02:39.827
from the full positive three charge.

00:02:39.827 --> 00:02:41.712
So there's two shielding electrons,

00:02:41.712 --> 00:02:45.028
so for a quick effective
nuclear charge calculation

00:02:45.028 --> 00:02:49.216
positive three minus two
gives us a value of plus one

00:02:49.216 --> 00:02:51.046
for the effective nuclear charge.

00:02:51.046 --> 00:02:53.847
So, it's like this outer
electron of lithium

00:02:53.847 --> 00:02:57.309
is feeling a nuclear charge of plus one,

00:02:57.309 --> 00:02:59.924
which pulls it toward the nucleus, right?

00:02:59.924 --> 00:03:02.506
So, there's an attractive
force between the outer

00:03:02.506 --> 00:03:04.589
electron and our nucleus.

00:03:06.647 --> 00:03:09.297
Now, the actual calculation for this um,

00:03:09.297 --> 00:03:10.130
Z is--

00:03:10.130 --> 00:03:13.089
S I should say, does not
have to be an integer,

00:03:13.089 --> 00:03:15.798
and the actual value for
lithium is approximately

00:03:15.798 --> 00:03:19.823
one point three, but our
quick, crude calculation

00:03:19.823 --> 00:03:21.579
tells us positive one.

00:03:21.579 --> 00:03:24.578
Let's do the same
calculation for beryllium,

00:03:24.578 --> 00:03:27.592
so the effective nuclear
charge for beryllium

00:03:27.592 --> 00:03:31.102
is equal to the number of protons, right,

00:03:31.102 --> 00:03:33.199
which for beryllium is positive four,

00:03:33.199 --> 00:03:37.263
and from that, we subtract
the number of inner electrons

00:03:37.263 --> 00:03:39.891
that are shielding the outer electrons.

00:03:39.891 --> 00:03:41.663
So, it's a similar situation,

00:03:41.663 --> 00:03:44.617
we have two inner electrons
that are shielding

00:03:44.617 --> 00:03:46.789
this outer electron, they're repelling

00:03:46.789 --> 00:03:48.220
this outer electron,

00:03:48.220 --> 00:03:51.275
shielding the outer electron
from the full positive

00:03:51.275 --> 00:03:53.557
four charge of the nucleus.

00:03:53.557 --> 00:03:55.866
SO we say there are two inner electrons,

00:03:55.866 --> 00:03:57.749
so the effective nuclear charge is

00:03:57.749 --> 00:03:59.862
positive four minus two,

00:03:59.862 --> 00:04:04.221
giving us an effective nuclear
charge of positive two.

00:04:04.221 --> 00:04:07.180
In reality, the effective
nuclear charge is

00:04:07.180 --> 00:04:10.422
approximately one point nine,

00:04:10.422 --> 00:04:13.103
and that's because beryllium
has another electron

00:04:13.103 --> 00:04:14.305
in its two s orbital over here,

00:04:14.305 --> 00:04:17.636
which does effect this
electron a little bit.

00:04:17.636 --> 00:04:19.227
It repels it a little bit,

00:04:19.227 --> 00:04:22.467
and so it actually deceases
the effective nuclear charge

00:04:22.467 --> 00:04:23.987
to about, one point nine.

00:04:23.987 --> 00:04:27.761
But again, for a quick
calculation, positive two works.

00:04:27.761 --> 00:04:30.232
So, the outer electron for beryllium,

00:04:30.232 --> 00:04:31.994
let's just choose this one again,

00:04:31.994 --> 00:04:34.074
is feeling an effective nuclear charge

00:04:34.074 --> 00:04:36.939
of positive two, which means that,

00:04:36.939 --> 00:04:39.874
it's going to be pulled
closer to the nucleus,

00:04:39.874 --> 00:04:43.773
there's a greater attractive
force on this outer electron

00:04:43.773 --> 00:04:46.907
for beryllium, as compared
to this outer electron

00:04:46.907 --> 00:04:48.080
for lithium.

00:04:48.080 --> 00:04:51.379
The effective nuclear
charge is only plus one

00:04:51.379 --> 00:04:53.441
for this outer electron,

00:04:53.441 --> 00:04:57.925
and because of this, the
beryllium atom is smaller, right?

00:04:57.925 --> 00:05:01.668
The two s orbital gets
smaller, and the atom itself

00:05:01.668 --> 00:05:02.501
is smaller.

00:05:02.501 --> 00:05:05.235
Beryllium is smaller than lithium.

00:05:05.235 --> 00:05:06.970
So this outer electron here,

00:05:06.970 --> 00:05:08.696
let me switch colors again,

00:05:08.696 --> 00:05:12.965
this outer electron for
beryllium is closer to

00:05:12.965 --> 00:05:16.341
the nucleus than the outer
electron for lithium.

00:05:16.341 --> 00:05:18.764
It feels a greater attractive force,

00:05:18.764 --> 00:05:20.770
and therefore it takes more energy

00:05:20.770 --> 00:05:25.451
to pull this electron away from
the neutral beryllium atom,

00:05:25.451 --> 00:05:28.560
and that's the reason for
the higher ionization energy.

00:05:28.560 --> 00:05:30.475
So beryllium has an ionization energy

00:05:30.475 --> 00:05:33.014
of positive 900 kilojoules per mole,

00:05:33.014 --> 00:05:37.674
compared to lithium's of
520 kilojoules per mole.

00:05:37.674 --> 00:05:41.954
So it has to do with the
effective nuclear charge.

00:05:41.954 --> 00:05:44.331
So far we've compared
lithium and beryllium

00:05:44.331 --> 00:05:46.706
and we saw that the ionization energy

00:05:46.706 --> 00:05:49.196
went from positive 520 kilojoules per mole

00:05:49.196 --> 00:05:51.657
to 900 kilojoules per mole,

00:05:51.657 --> 00:05:53.494
and we said that was because of the

00:05:53.494 --> 00:05:56.223
increased effective nuclear
charge for beryllium,

00:05:56.223 --> 00:05:59.172
but as we go from beryllium to boron,

00:05:59.172 --> 00:06:01.646
there's still an increased
effective nuclear charge,

00:06:01.646 --> 00:06:04.007
but notice our ionization energy goes

00:06:04.007 --> 00:06:06.856
from 900 kilojoules per mole for beryllium

00:06:06.856 --> 00:06:10.054
to only 800 kilojoules per mole for boron,

00:06:10.054 --> 00:06:13.359
so there's a slight decrease
in the ionization energy.

00:06:13.359 --> 00:06:16.346
And let's look at the electron
configuration of boron

00:06:16.346 --> 00:06:18.116
to see if we can explain that.

00:06:18.116 --> 00:06:19.848
Boron has five electrons,

00:06:19.848 --> 00:06:22.486
so the electron
configuration is one s two,

00:06:22.486 --> 00:06:24.735
two s two, and two p one.

00:06:24.735 --> 00:06:28.356
So that fifth electron
goes into a two p orbital,

00:06:28.356 --> 00:06:31.607
and the two p orbital is higher in energy

00:06:31.607 --> 00:06:33.681
than a two s orbital, which means

00:06:33.681 --> 00:06:35.950
the electron in the two p orbital

00:06:35.950 --> 00:06:38.877
is on average, further
away from the nucleus

00:06:38.877 --> 00:06:41.816
that the two electron
in the two s orbital.

00:06:41.816 --> 00:06:43.652
So if we just sketch
this out really quickly,

00:06:43.652 --> 00:06:45.378
let's say that's my two s orbital,

00:06:45.378 --> 00:06:47.279
I have two electrons in there,

00:06:47.279 --> 00:06:49.642
and this one electron in the two p orbital

00:06:49.642 --> 00:06:53.580
is on average further
away from the nucleus.

00:06:53.580 --> 00:06:57.406
So, those two electrons
in the two s orbital

00:06:57.406 --> 00:07:01.764
actually can repel this
electron in the two p orbital.

00:07:01.764 --> 00:07:04.404
So, there's a little bit
extra shielding there

00:07:04.404 --> 00:07:08.552
of the two p electron
from the full attraction

00:07:08.552 --> 00:07:10.927
of the nucleus, right?

00:07:10.927 --> 00:07:13.430
So, even though we have
five protons in the nucleus,

00:07:13.430 --> 00:07:15.901
and a positive five charge for boron,

00:07:15.901 --> 00:07:18.357
the fact that these two s electrons

00:07:18.357 --> 00:07:20.800
add a little bit of extra shielding means

00:07:20.800 --> 00:07:24.378
it's easier to pull this electron away.

00:07:24.378 --> 00:07:27.059
So, it turns out to be a
little bit easier to pull

00:07:27.059 --> 00:07:29.019
this electron in the two p orbital away

00:07:29.019 --> 00:07:31.192
due to these two s electrons.

00:07:31.192 --> 00:07:33.568
And that's the reason
for this slight decrease

00:07:33.568 --> 00:07:35.711
in ionization energy.

00:07:35.711 --> 00:07:37.456
As we go from boron to carbon,

00:07:37.456 --> 00:07:39.736
we see an increase in ionization energy,

00:07:39.736 --> 00:07:41.347
from carbon to nitrogen,

00:07:41.347 --> 00:07:43.488
an increase in ionization energy.

00:07:43.488 --> 00:07:45.603
Again, we attribute that to increased

00:07:45.603 --> 00:07:48.286
effective nuclear charge,

00:07:48.286 --> 00:07:50.560
but when we go from nitrogen to oxygen,

00:07:50.560 --> 00:07:52.471
we see a slight decrease again.

00:07:52.471 --> 00:07:54.832
From about 1400 kilojoules per mole,

00:07:54.832 --> 00:07:58.551
down to about 1300 kilojoules
per mole for oxygen.

00:07:58.551 --> 00:08:01.961
So, let's see if we can
explain that by writing out

00:08:01.961 --> 00:08:06.020
some electron configurations
for nitrogen and oxygen.

00:08:06.020 --> 00:08:10.365
Nitrogen has seven
electrons to think about.

00:08:10.365 --> 00:08:12.366
So it's electron configuration is

00:08:12.366 --> 00:08:15.533
one s two, two s two, and two p three.

00:08:18.172 --> 00:08:20.484
So that takes care of all seven electrons.

00:08:20.484 --> 00:08:23.626
For oxygen, we have another electron, so

00:08:23.626 --> 00:08:26.975
one s two, two s two, two p four

00:08:26.975 --> 00:08:29.993
is the electron configuration for oxygen.

00:08:29.993 --> 00:08:32.510
Let's just draw using orbital notation

00:08:32.510 --> 00:08:35.645
the two s orbital and the two p orbital.

00:08:35.645 --> 00:08:38.748
So for nitrogen, here's our two s orbital.

00:08:38.748 --> 00:08:40.418
We have two electrons in there,

00:08:40.418 --> 00:08:42.589
so let's draw in our two electrons.

00:08:42.589 --> 00:08:44.459
And for our two p orbitals,

00:08:44.459 --> 00:08:45.791
we have three electrons.

00:08:45.791 --> 00:08:48.360
So here are the two p orbitals,

00:08:48.360 --> 00:08:52.072
and let's draw in our three electrons

00:08:52.072 --> 00:08:53.999
using orbital notation.

00:08:53.999 --> 00:08:55.930
Let's do the same thing for oxygen.

00:08:55.930 --> 00:08:58.183
So there's the two s orbital
for oxygen, which is full,

00:08:58.183 --> 00:09:00.760
so we'll sketch in those two electrons,

00:09:00.760 --> 00:09:04.910
and we have four electrons
in the two p orbitals.

00:09:04.910 --> 00:09:06.987
So let me draw in the two p orbitals.

00:09:06.987 --> 00:09:08.137
There's one electron,

00:09:08.137 --> 00:09:10.113
there's two, there's three,

00:09:10.113 --> 00:09:13.131
and notice what happens when
we add the fourth electron.

00:09:13.131 --> 00:09:15.456
We're adding it to an orbital that already

00:09:15.456 --> 00:09:17.665
has an electron in it,

00:09:17.665 --> 00:09:21.937
so when I add that fourth
electron to the two p orbital,

00:09:21.937 --> 00:09:24.971
it's repelled by the electron
that's already there,

00:09:24.971 --> 00:09:28.478
which means it's easier to
remove one of those electrons,

00:09:28.478 --> 00:09:30.505
so electrons have like charges,

00:09:30.505 --> 00:09:32.513
and like charges repel.

00:09:32.513 --> 00:09:34.340
And so that's the reason for this

00:09:34.340 --> 00:09:37.297
slight decrease in ionization energy.

00:09:37.297 --> 00:09:40.538
So, it turns out to be a little bit easier

00:09:40.538 --> 00:09:43.052
to remove an electron from an oxygen atom,

00:09:43.052 --> 00:09:45.905
than nitrogen, due to this repulsion

00:09:45.905 --> 00:09:47.829
in this two p orbital.

00:09:47.829 --> 00:09:51.552
From there on, we see
our general trend again.

00:09:51.552 --> 00:09:55.542
The ionization energy for
fluorine is up to 1681,

00:09:55.542 --> 00:09:58.264
and then again for
neon, we see an increase

00:09:58.264 --> 00:10:00.749
in the ionization energy due to

00:10:00.749 --> 00:10:02.809
the increased effective nuclear charge.


Hinduism Introduction: Core ideas of Brahman, Atman, Samsara and Moksha

WEBVTT
Kind: captions
Language: en

00:00:00.342 --> 00:00:02.670
- [Instructor] We're now
going to talk about Hinduism

00:00:02.670 --> 00:00:05.692
which is one of the
largest religions on Earth,

00:00:05.692 --> 00:00:07.807
practiced by over a billion people.

00:00:07.807 --> 00:00:10.311
And, it's interesting for several reasons.

00:00:10.311 --> 00:00:12.497
First, it is considered to be one of the

00:00:12.497 --> 00:00:15.326
oldest religions that is still practiced.

00:00:15.326 --> 00:00:18.211
Some historians would place the origins

00:00:18.211 --> 00:00:21.936
of Hinduism at 5,000 years into the past.

00:00:21.936 --> 00:00:24.442
It has elements that
may have been practiced

00:00:24.442 --> 00:00:26.441
in the Indus Valley civilization.

00:00:26.441 --> 00:00:28.594
You also have significant
elements that come

00:00:28.594 --> 00:00:29.982
from the Vedic Period.

00:00:29.982 --> 00:00:33.405
In fact, the Vedas, for which
the Vedic Period is named

00:00:33.405 --> 00:00:38.199
really form the root of Hinduism
as it is practiced today.

00:00:38.199 --> 00:00:40.465
It is believed that the Vedas come from

00:00:40.465 --> 00:00:43.255
an Indo-Aryan people that many historians

00:00:43.255 --> 00:00:46.732
believe came from Central
Asia and were related

00:00:46.732 --> 00:00:49.573
to many of the people
who colonized Europe.

00:00:49.573 --> 00:00:51.522
Now, the other thing that is fascinating

00:00:51.522 --> 00:00:53.696
about Hinduism, and I really just referred

00:00:53.696 --> 00:00:57.460
to some of it, it is a
combination of many cultures

00:00:57.460 --> 00:01:01.070
that really merged over
thousands of years.

00:01:01.070 --> 00:01:04.639
And, they merged around
the Indian subcontinent.

00:01:04.639 --> 00:01:06.637
As you will see there are many traditions,

00:01:06.637 --> 00:01:10.579
many cultures, many
different ways that one can,

00:01:10.579 --> 00:01:13.987
and many different ways that
people do practice Hinduism.

00:01:13.987 --> 00:01:16.173
But, there are also core
beliefs that we wanna get

00:01:16.173 --> 00:01:17.822
to the heart of in this video.

00:01:17.822 --> 00:01:20.213
And, we'll discuss more in future videos.

00:01:20.213 --> 00:01:22.802
Now, what's also interesting
is where the name

00:01:22.802 --> 00:01:26.105
Hinduism or Hindu comes
from, a Hindu being someone

00:01:26.105 --> 00:01:28.191
who practices Hinduism.

00:01:28.191 --> 00:01:31.651
The name for what we
now call the Indus River

00:01:31.651 --> 00:01:36.269
in Sanskrit was Sindhu,
and Sindh is still a region

00:01:36.269 --> 00:01:38.058
in the Indian subcontinent.

00:01:38.058 --> 00:01:41.051
The version that the
Persians said was Hindus

00:01:41.051 --> 00:01:44.567
and this got converted to Indus in Latin.

00:01:44.567 --> 00:01:49.180
So really, Hinduism is
the term for the cultural

00:01:49.180 --> 00:01:53.347
and religious practices of
people beyond the Indus River.

00:01:54.614 --> 00:01:57.137
The India really comes
from this same root.

00:01:57.137 --> 00:02:00.996
Indus is where India comes
from, but Indus comes from

00:02:00.996 --> 00:02:03.959
Hindus, which comes from
Sindhu and these are all

00:02:03.959 --> 00:02:05.632
related to the word Hindu.

00:02:05.632 --> 00:02:08.791
And, you can see that very
clearly in the Persian version.

00:02:08.791 --> 00:02:11.476
Now, as I mentioned, there's
many different practices

00:02:11.476 --> 00:02:14.167
in Hinduism, many different
traditions, many different

00:02:14.167 --> 00:02:17.759
rituals in Hinduism, but
I'm going to try to focus

00:02:17.759 --> 00:02:21.620
in on what could be
considered the spiritual core.

00:02:21.620 --> 00:02:24.656
And, a lot of this comes out of the Vedas.

00:02:24.656 --> 00:02:27.277
They're a collection of hymns, rituals,

00:02:27.277 --> 00:02:29.021
but also philosophy.

00:02:29.021 --> 00:02:32.316
And, the subset of the Vedas
that are very concerned

00:02:32.316 --> 00:02:34.727
with the spiritual and the philosophical

00:02:34.727 --> 00:02:38.274
are known as the Upanishads,
which means sitting down

00:02:38.274 --> 00:02:39.236
or coming near to.

00:02:39.236 --> 00:02:41.225
Some people say coming near to God,

00:02:41.225 --> 00:02:44.867
some people say coming
near to the actual reality,

00:02:44.867 --> 00:02:48.156
or coming near to a
teacher as in sitting down

00:02:48.156 --> 00:02:51.156
to get a lesson or to have a dialog.

00:02:51.156 --> 00:02:54.399
Now, the central idea in Hinduism

00:02:54.399 --> 00:02:56.316
is the idea of Brahman.

00:02:57.235 --> 00:03:01.402
And Brahman should not be
confused with the god Brahma.

00:03:03.018 --> 00:03:06.249
Brahma is sometimes, you
could view, as a aspect

00:03:06.249 --> 00:03:10.176
of a Brahman, but Brahman
is viewed as the true

00:03:10.176 --> 00:03:11.621
reality of things.

00:03:11.621 --> 00:03:14.950
It is shapeless, genderless, bodiless,

00:03:14.950 --> 00:03:16.477
it cannot be described.

00:03:16.477 --> 00:03:18.727
It can only be experienced.

00:03:19.561 --> 00:03:23.046
Now, according to Hindu belief we are all

00:03:23.046 --> 00:03:25.152
part of Brahman.

00:03:25.152 --> 00:03:28.505
And, what we perceive as our individuality

00:03:28.505 --> 00:03:32.356
is really, you can consider
to be a quasi-illusion.

00:03:32.356 --> 00:03:36.187
So, this might be one
individual right over here

00:03:36.187 --> 00:03:40.354
and then we might have another
individual right over here.

00:03:41.254 --> 00:03:44.307
And, this separateness,
the illusion of the reality

00:03:44.307 --> 00:03:48.474
that we see around us this
is referred to as Maya.

00:03:49.446 --> 00:03:53.282
And, Maya is not just the
illusion or the quasi-illusion

00:03:53.282 --> 00:03:55.959
created by our senses it is even notions

00:03:55.959 --> 00:03:58.385
like our ego, our identity.

00:03:58.385 --> 00:04:01.566
And, within that context
that inner self, the thing

00:04:01.566 --> 00:04:04.736
that is even within
our, that is even deeper

00:04:04.736 --> 00:04:06.360
than our sense of identity.

00:04:06.360 --> 00:04:08.777
This is referred to as Atman.

00:04:09.819 --> 00:04:12.638
And, as you can see they way
it's been diagrammed here,

00:04:12.638 --> 00:04:15.460
the way we've drawn it
out Atman is essentially

00:04:15.460 --> 00:04:17.508
the same thing as Brahman.

00:04:17.508 --> 00:04:20.445
And, oftentimes you
will see it referred to

00:04:20.445 --> 00:04:25.112
as Atman-Brahman, they're
really the same thing

00:04:25.112 --> 00:04:27.946
but it's really, it's
an illusion that there

00:04:27.946 --> 00:04:31.266
is this separateness of our reality.

00:04:31.266 --> 00:04:34.849
Now, according to Hindu
belief in each life

00:04:36.211 --> 00:04:39.821
you have this core part of
yourself which is Atman,

00:04:39.821 --> 00:04:41.613
which is part of Brahman.

00:04:41.613 --> 00:04:44.905
And, when you die it doesn't disappear,

00:04:44.905 --> 00:04:49.016
but it will take on or
it will subjugate itself

00:04:49.016 --> 00:04:50.599
to another reality.

00:04:55.585 --> 00:04:58.362
So, after death this
individual or this perceived

00:04:58.362 --> 00:05:01.888
individual might take on another identity

00:05:01.888 --> 00:05:03.094
in another reality.

00:05:03.094 --> 00:05:06.408
They would perceive it as another life.

00:05:06.408 --> 00:05:08.902
And, this notion of
one life after another,

00:05:08.902 --> 00:05:11.772
one reality after another is sometimes

00:05:11.772 --> 00:05:15.052
referred to as transmigration of the soul,

00:05:15.052 --> 00:05:18.676
sometimes referred to reincarnation,

00:05:18.676 --> 00:05:23.240
or this notion of Samsara,
which is this endless cycle

00:05:23.240 --> 00:05:25.426
of birth and rebirth.

00:05:25.426 --> 00:05:28.398
It really comes from this
notion of same flowing,

00:05:28.398 --> 00:05:31.714
this thing, this pattern
that goes on and on and on.

00:05:31.714 --> 00:05:35.809
And, according to Hindu
belief what that next life is,

00:05:35.809 --> 00:05:39.645
what that next reality is
is based on your actions

00:05:39.645 --> 00:05:41.450
in this life.

00:05:41.450 --> 00:05:44.331
Karma, literally is referring to actions,

00:05:44.331 --> 00:05:47.503
but it's really actions
driving consequences

00:05:47.503 --> 00:05:51.234
not only in this reality
but in the next reality.

00:05:51.234 --> 00:05:53.895
Now, there's another notion of Dharma.

00:05:53.895 --> 00:05:57.656
Dharma is based on what is
the role you should play

00:05:57.656 --> 00:06:02.197
given the reality, given
the life that you are in.

00:06:02.197 --> 00:06:04.257
So, in a very simplified
way you could say,

00:06:04.257 --> 00:06:07.495
"Well, Dharma is the rightful
role, the rightful actions,

00:06:07.495 --> 00:06:10.634
"your duty depending on your role,

00:06:10.634 --> 00:06:12.739
"depending on your reality."

00:06:12.739 --> 00:06:17.183
Karma is how that action
translates into consequences

00:06:17.183 --> 00:06:20.328
which is going to drive what
happens in this endless cycle.

00:06:20.328 --> 00:06:23.984
Now, a core idea of
Hinduism is to try to escape

00:06:23.984 --> 00:06:28.339
from this cycle, to awaken
to the true reality,

00:06:28.339 --> 00:06:30.893
awaken from this quasi-reality.

00:06:30.893 --> 00:06:33.233
And, this is really one
of the central ideas

00:06:33.233 --> 00:06:37.991
of the Upanishads that
eventually if you can awaken,

00:06:37.991 --> 00:06:41.309
so let's say that this is
an awakening, this entity,

00:06:41.309 --> 00:06:43.870
this Atman, this self right over here,

00:06:43.870 --> 00:06:46.549
this perceived individual has now awoken

00:06:46.549 --> 00:06:50.215
and can see through, pierces
the veil of that Maya.

00:06:50.215 --> 00:06:54.537
Now, they have rejoined
Brahman and they've recognized

00:06:54.537 --> 00:06:57.349
that Atman and Brahman are the same.

00:06:57.349 --> 00:07:00.402
And, this freeing from Samsara, from this

00:07:00.402 --> 00:07:03.386
birth death cycle, this is

00:07:03.386 --> 00:07:05.219
referred to as Moksha.

00:07:08.674 --> 00:07:11.943
Now, to make this idea
a little bit clearer

00:07:11.943 --> 00:07:16.668
let's look at some quotes
from the actual Upanishads.

00:07:16.668 --> 00:07:20.798
So, this is two versions
from the Isha Upanishad

00:07:20.798 --> 00:07:23.855
and the reason why I like
to show it is because

00:07:23.855 --> 00:07:27.042
it shows that if you're
translating from Sanskrit

00:07:27.042 --> 00:07:29.526
into English or really from
any one language into another

00:07:29.526 --> 00:07:31.637
there's gonna be some
room for interpretation

00:07:31.637 --> 00:07:32.787
but we can see it here.

00:07:32.787 --> 00:07:35.708
So, this is from the Isha
Upanishad which is considered

00:07:35.708 --> 00:07:37.073
one of most important ones.

00:07:37.073 --> 00:07:40.192
It's a subset, it's a
section of the Yajurveda,

00:07:40.192 --> 00:07:42.547
one of the four early Vedas.

00:07:42.547 --> 00:07:44.880
And, they write, and this
is an English translation,

00:07:44.880 --> 00:07:49.531
"The wise man beholds all beings
in the self, or the Atman,

00:07:49.531 --> 00:07:52.382
"and the self in all
beings, for that reason

00:07:52.382 --> 00:07:53.983
"he does not hate anyone.

00:07:53.983 --> 00:07:57.668
"To the seer all things
have verily become the self.

00:07:57.668 --> 00:08:00.621
"What delusion, what
sorrow can there be for him

00:08:00.621 --> 00:08:02.672
"who beholds that oneness?"

00:08:02.672 --> 00:08:05.627
This is another version of the same verses

00:08:05.627 --> 00:08:07.673
from the Isha Upanishad.

00:08:07.673 --> 00:08:10.772
"He who sees all beings
in the self and the self

00:08:10.772 --> 00:08:14.774
"in all beings he never
turns away from it, the self.

00:08:14.774 --> 00:08:17.877
"For, he who percieves
all beings as the self

00:08:17.877 --> 00:08:19.989
"how can there be delusion or grief

00:08:19.989 --> 00:08:23.172
"when he sees this oneness everywhere."

00:08:23.172 --> 00:08:25.916
So, I might be getting into
an argument with someone

00:08:25.916 --> 00:08:28.947
but deep down if I
recognize that both myself

00:08:28.947 --> 00:08:33.341
and that individual that we
are part of this same Brahman

00:08:33.341 --> 00:08:36.499
that he is me and I am it, or I am he,

00:08:36.499 --> 00:08:40.638
well then that anger seems
a little bit misguided.

00:08:40.638 --> 00:08:43.047
Now, to get a little bit more context on

00:08:43.047 --> 00:08:46.260
this notion of oneness
here's another verse

00:08:46.260 --> 00:08:49.297
from Chandogya Upanishad,
which is also considered

00:08:49.297 --> 00:08:51.505
one of the significant Upanishads.

00:08:51.505 --> 00:08:54.172
And, it's part of the Sama Veda.

00:08:55.882 --> 00:08:59.498
"As the rivers flowing east
and west merge in the sea

00:08:59.498 --> 00:09:02.924
"and become one with it,
forgetting they were separate

00:09:02.924 --> 00:09:06.954
"rivers, so do all creatures
lose their separateness

00:09:06.954 --> 00:09:11.121
"when they merge at last into
pure Being," into Brahman.

00:09:12.239 --> 00:09:15.336
"There's nothing that
does not come from him."

00:09:15.336 --> 00:09:17.151
And, the use of the word him is really

00:09:17.151 --> 00:09:20.634
an anthropomorphism of
this notion that has

00:09:20.634 --> 00:09:23.384
really no gender or body or form.

00:09:24.432 --> 00:09:27.631
"Of everything he is the inmost Self.

00:09:27.631 --> 00:09:30.923
"He is the truth, he is the Self supreme.

00:09:30.923 --> 00:09:34.820
"You are that Shvetaketu, you are that."

00:09:34.820 --> 00:09:37.456
And, this last verse is
referring it's in this

00:09:37.456 --> 00:09:40.560
Chandogya Upanishad it's
a conversation between

00:09:40.560 --> 00:09:41.774
the teacher and his son.

00:09:41.774 --> 00:09:44.024
And, the son is Shvetaketu,

00:09:45.415 --> 00:09:47.444
my apologies for pronunciation.

00:09:47.444 --> 00:09:50.788
So, what's he's saying is that
these rivers is an analogy

00:09:50.788 --> 00:09:54.234
for you and I and we might
see ourselves as different

00:09:54.234 --> 00:09:56.032
but at some point we will flow

00:09:56.032 --> 00:09:57.929
and become one with the ocean.

00:09:57.929 --> 00:10:01.282
And, he's pointing out to his
son, you are not different

00:10:01.282 --> 00:10:03.994
from that, you are self, you are Ahtman.

00:10:03.994 --> 00:10:07.161
It is Brahman, it is one and the same.