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The Matrix. You gotta remember the, uh, the humans floating
in vats of KY jelly? Tubes and wires keeping them alive, stimulating
their brains, to make them believe that they were experiencing the real world â the world
we all think we know? Well, almost-20-year-old spoiler alert here: some of
them come to find out that the real world was a desolate wasteland, and the lives everyone thought they were living were just fabrications fed into their brains. A select few were ârescuedâ from the illusion,
but some of them were so unhappy in the real world that they chose to return to illusion. But Neo -- and the others who chose to stay
and fight --- were the philosophical heroes of the movie, choosing truth at the cost of
comfort and happiness. After watching The Matrix, you mightâve
found yourself wondering: Could this be true? Could we possibly be stuck in a dream world
of someone elseâs making, with no way to tell that our ârealityâ isnât real at
all? If so, youâre not the first person to have
wondered about these things. In fact, the original Neo? The guy who really
went into battle against the matrix of illusion, in order to defend the Truth? He was a 17th century mathematician. Named
Rene. [Theme Music] Last time, we talked about Plato, and his
belief that the ordinary reality of the material world is only a shadowy approximation of Ultimate
Reality. Socrates, meanwhile, who was widely believed to be the wisest man in Athens, fretted about how little he knew. Philosophers spend a lot of time obsessing
about knowledge, wishing they knew more, and worrying that theyâre wrong about what they
think they know. They even, if you remember from the first
episode, have a fancy name for the study of knowledge â epistemology. The philosopher who gets the gold star for
taking this how-do-I-know-what-I-know paranoia to astonishing levels is the early modern philosopher, scientist, and mathematician, Rene Descartes. When you watch The Matrix, you should congratulate the Wachowskis for giving us such a great sci-fi adventure story. But you should also remember that the archetype
of the story actually has its roots all the way back in the writings of Descartes, in
the early 1600s. For a story like The Matrix to get off the
ground, the audience has to be willing to entertain some level of skepticism. And a skeptic is someone who questions whether
itâs possible to know anything with certainty. And Descartes was the mac daddy of all skeptics. He was so skeptical, named a form of skepticism
after him â Cartesian Skepticism! Why was Descartes so skeptical? Well, he realized that many of the beliefs
he used to hold were actually false. We all go through this; itâs part of what we call
growing up. Learning the horrible truth about Santa and
the tooth fairy. That you canât actually buy everything you want and need for just $100.
That your parents don't really have all the answers. But realizing that he used to believe things
that were false really got Descartes to thinking. Because: When he believed those things, he
didnât realize they were false. So what if some of the things he still believed were also false, and he just hadnât realized it yet? How could he know that his beliefs were true? Well, after a bit of a freak out, Descartes
realized that the only way to make sure he wasnât holding any false beliefs was to
disbelieve everything. At least temporarily. He offered this as an analogy: Imagine you
have a basket of apples, and youâre concerned that some of the apples might be rotten. Since the rot could spread and ruin the fresh
apples, the only way to make sure thereâs no rot in the basket is to dump out all the
fruit, inspect each apple in turn, and return only the fresh apples to the basket. Knowing that, just like rotten fruit, a rotten idea
can spread and infect all the ideas around it, Descartes up-ended the apple basket of
his beliefs and decided to start from scratch. If he examined each possible belief carefully,
and only accepted those about which there could be no doubt, then heâd know he was
believing only true things. So, Descartes began the arduous task of examining
his beliefs one by one. He started with empirical beliefs â things we come to know directly through the use of our senses. And many of us think that our senses are the
most reliable source of information. If I can see it, and hear it, touch it, taste it,
smell it, I must know it, right? Not so much. Descartes pointed out that our
senses fail us all the time. You rush to catch up to a friend and realize,
as she turns around, that your eyes played some tricks on you, and youâve just tapped
the shoulder of a perfect stranger. Food tastes wrong when youâre sick. Drink
too much and you feel like the room is spinning. Water thatâs room temperature feels hot
when you come inside after playing in the snow. The list goes on â you can probably think of countless times when your senses gave you faulty information. And once you realize that, how can you ever
trust your senses again? And for Descartes, disbeliever of everything,
iit got worse. Have you ever had a dream so vivid you thought
you were awake? Youâve probably had a dream that you were
dreaming, or dreamed that you woke up from a dream, but in fact were still in the dream. Not everyone has had these experiences, but
many of us have, and given that we donât always know that weâre dreaming while itâs
happening... HOW DO WE KNOW WEâRE NOT DREAMING RIGHT
NOW?! Maybe you just think youâre watching Crash Course,
but in fact, youâre cozied up in bed, dreaming about me. Which, hey, like, who could blame you? But really, when you think about it, can you
be SURE itâs not the case? Now, you might be thinking, ok, sure, I probably
deceive myself from time to time, without knowing Iâm doing it. But dreams end. And
when I wake up, I realize that what I thought I was experiencing was all in my head. And the same is true for when my senses let
me down. Those are just temporary instances, isolated
to a particular situation. As soon as the situation changes, I can realize that my experience
was false. This quality â the ability to check in with
yourself and figure out that youâre experiencing a deception â describes what Descartes called
local doubts. Those are doubts about a particular sense experience, or some other occurrence at a particular point in time. Step out of that point, and you can check
to determine if youâve been deceived. But what if ... EVERYTHING IS A DECEPTION? What if everyone is experiencing the same
false reality, from birth until death? What if nothing is as it seems, just like in The
Matrix? This type of doubt, the kind you canât step out of,
and thus canât check, is called global doubt. And itâs the subject of this weekâs Flash Philosophy.
Letâs go to the Thought Bubble. Philosopher Bertrand Russell illustrated the
concept of global doubt with this troubling thought: What if the universe was created just five
minutes ago? In this scenario, known as the Five Minute
Hypothesis, the creator of the universe could have designed many elements of the world to
make them appear âpre-worn,â so as to seem old. From dinosaur bones â fashioned by the creator,
and planted for us to find, to that scar on your knee â put there by the creator, along with
the pre-loaded false memory of how you got it. It seems crazy, but thereâs just no way
to prove that it isnât the case. The question for Russell was -- does it matter?
Descartes thought it did. But as a good Catholic, he couldnât fathom
a world in which God would plant globally false beliefs in all of our minds. So instead, he posited the existence of an
Evil Genius, whose purpose in life was to deceive us, and who was clever enough to do it. Descartes didnât exactly think such a being
was likely to exist. But he realized there was no way to rule out his existence. And
as long as an Evil Genius was possible, he worried that we were all stuck. Stuck in a radical skepticism, in which we really cannot trust any of our beliefs. Everything we believe, every sense experience, every thought, they could all have been put in our minds by the Evil Genius, who created an illusory world so seamless, weâd have no way of detecting the illusion. Just like the machines created for the characters
in The Matrix. Descartes was at the point of despair. But then...he realized something. He had cause to doubt everything. Everything EXCEPT the fact that he was doubting. He knew he was doubting. He could be sure
of that. And if he was doubting, then he must exist
â at least as a thinking thing. After all, a doubt is a thought, and if there is thought, there must be a thinker having those thoughts. So Descartes decided that he couldnât know
that he had a body â what he believed to be his body couldâve been part of the Evil Geniusâ deception. But he must have had a mind, or he couldnât have been having these thoughts.
This was Descartesâs ah-ha moment. In his book, Meditations on First
Philosophy, he declared: Cogito ergo sum.
âI think, therefore, I am.â Itâs one of the most famous realizations
in philosophy â I cannot doubt my own existence. I can doubt everything else, but I canât
doubt I am, bare minimum, a mind having thoughts. This was Descartesâ foundational belief,
the first belief he put back in his apple basket. And from there, he figured he could
build back up to more certain beliefs. Once he was certain that he was a thinking
thing, he began examining his thoughts. And one of his most clear thoughts â what he called
a clear and distinct idea â was that God exists. He gave an argument for this â which weâre
going to examine in a later episode. But for now, take my word for it â itâs
got some problems. And from there, he considered his beliefs about the physical world, and concluded that it, too, actually exists. Ultimately, he determined, God wouldnât
allow him to have clear and distinct ideas that were false, without some way to detect
his own error. So, he concluded, the Evil Genius is not actually fabricating lies that
consume our every waking moment. Descartes managed to reason from âcogitoâ
all the way back up to having basically all the beliefs he started with, back in his apple
basket. Which is the story of how Rene Descartes, with the power of skepticism, defeated the threat of the Evil Genius. Much like how Neo ultimately short-circuited the Matrix, though considerably less impressive to watch, I imagine. He found certainty through his discovery of
the one belief that he simply couldnât doubt â his own existence as a thinking thing. But, there is a lot of debate among philosophers
as to whether Descartes actually manages to justifiably believe anything other than
that he exists as a thinking thing. And weâll talk more about that more next time. This episode of Crash Course Philosophy is
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Descartes was a sceptic? I know he used his own method of scepticism in order to find certainties, but I always thought sceptics say that there are NO truths.
This is my first time hearing about radical skepticism really extreme. I think that's a good thing about philosophy is that no idea is really wrong as crazy as it can sound