Hi Alex here. What is sustainability? You
must have heard a lot about
sustainability and sustainable
development over the last few years.
I know I did. And maybe, just maybe,
sometimes you were not totally clear as
to what people really meant. So here is a
definition that my workshop participants
have found very clear and useful over
the years. You may be familiar with the
Brundtland definition which is quite
common. "Sustainable development is
development that meets the needs of the
present without compromising the ability
of future generations to meet their own
needs". Although this does not exactly
tell us what to do on Monday morning,
it's a very easy definition to
understand and to communicate. There's
another one that was created in the late
1980s that is more of a scientific
definition. It was created by a Swedish
doctor who found that there was a lack
of common language around sustainability.
So he thought what if we managed to get
a group of scientists together and
to agree on what sustainability means based on science and thermodynamics. And maybe
that will lead to understanding what the
root causes of unsustainability are.
So that's what he did. He put together a
group of 50 scientists, mathematicians
physicists, and chemists, etc. and after 22
draft, they agreed on several things:
First they agreed on the fact that we
live in the biosphere. The biosphere is
this very thin layer at the surface of
the earth where life is possible.
Proportionally speaking, it is a thin and
fragile as the skin on an onion. And
within this biosphere, there are plants
and animals. Plants produce oxygen and
food, which are consumed by the animals. In return, animals produce fertilizer and
CO2 (carbon dioxide) which are used by the plants and we have a cycle that is well
balanced. This is a very quick cycle : we
eat every day and we breathe every
second, and it works well.
Then, they agreed on the fact that this
system, the biosphere, is open with
respect to energy.
This means that energy from the Sun
comes in and radiations come out. This is
also known as the first law of
thermodynamics. They also agreed on the
fact that this system is closed with
respect to matter. So maybe you remember
this very famous phrase from Lavoisier
that says "nothing is created, nothing
disappears, everything is only
transformed". This is also known as the
law of conservation of matter and it
means that except for a few satellites
and meteorites, the matter that was on
Earth four billion years ago is still
here today. It has changed form and the
molecules have reorganized themselves
but it is still the same matter. The
other thing that comes with this, is that
everything has a tendency to disperse.
For example, take an iPhone and wait for
a million years, it's very likely that
you will get a pile of dust. Take a pile
of dust and wait for a million years, you
will never get an iPhone. It works only
in one direction. This is also known as
the second law of thermodynamics : the law
of entropy. So if everything disperses
all the time, how is it possible that we
live here in such a beautiful world with
beautiful nature, cities, people, flowers
and so on. Well, this is what
photosynthesis does for us.
Photosynthesis pays the bills. Plants
have the capacity to use the energy from
the Sun in order to produce oxygen and
sugar using carbon dioxide and water.
Photosynthesis reorganizes matter and
creates new structure. The group of
scientists also agreed on the fact that
there are other cycles, very slow
geological cycles, that bring matter from
the lithosphere, that we also call the
Earth's crust, to the biosphere and these
cycles are also very well balanced.
Some matter moves from the Earth's crust to the biosphere through things like
volcano eruptions and weathering, and
just about the same amount of matter
goes back from the biosphere to the
Earth's crust, via
things like mineralization and
sedimentation. And all this is very well
balanced. This cycles take millions of
years, they are very slow, unlike the
previous ones, and they also work well. So this is what the scientific community
agreed upon. This is the world we live.
So what is sustainability? Well, it is
actually the capacity of our human
society to continue indefinitely within
these natural cycles. And sustainable
development would be a development
toward this state of sustainability. So
you may be thinking "well this does not
exactly tell us what to do on Monday
morning either". That's right but it made
it possible for our group of scientists
to look at the things that we do to
interfere with these natural cycles and
they found four root causes of
unsustainability. And these are the four
things that we need to stop doing to be
sustainable. They are all equally
important. They're all necessary and
sufficient. The first one is that we
extract large flows of materials from
the Earth's crust, the lithosphere. These materials are
things like oil, like natural gas, heavy
metals, etc. that are rare in the
biosphere and that we extract in such
large quantities that they accumulate
and nature cannot cope. The second one is that we create, in our society, substances
that accumulate in nature. We create
chemical compound that nature takes a
very long time to break down but we also
create substances that already exist in
nature, like carbon dioxide for example,
but in such large quantities, that they
accumulate and nature cannot cope. The
third one is that we physically inhibit
nature's ability to run the natural
cycles. How do we do that? Well, for example,
by chopping trees at a faster rate that
they can grow, by systematically
destroying ecosystems and replacing them with parking lots, roads, buildings etc. so
that nature cannot run its cycles
anymore.
These are three ecological root causes.
Once again, there is no priority order.
The fourth one is social and can
actually be the most important of all. We
create in our society barriers to people
meeting their basic human needs
worldwide. Human needs are very
interesting and you can watch our video
about them if you are interested. There
are things like creativity, identity,
participation, and so o,n and so forth. So
how do we do that? Well, for example if
you purchase a product that is
manufactured in a sweatshop in a
developing country, indirectly, you
support the business, and indirectly, you
contribute to poor working conditions in
this factory, and to the fact that these
people are unable to meet their basic
human needs. So this is the scientific
consensus on the four root causes of
unsustainability. I hope it helps you
understand better what sustainability
means and the fundamental reasons why
we're not sustainable today. You will
find many other engaging sustainability
videos to learn and teach on our website
sustainabilityillustrated.com. If
sustainability education is important to
you, please subscribe and consider making
a pledge of $1.00 or more on our patreon
page and thank you for watching.
