Why does the universe exist?
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0:01 - 0:03Why does the universe exist?
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0:03 - 0:07Why is there — Okay. Okay. (Laughter)
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0:07 - 0:10This is a cosmic mystery. Be solemn.
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0:10 - 0:13Why is there a world, why are we in it,
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0:13 - 0:15and why is there something rather than nothing at all?
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0:15 - 0:20I mean, this is the super ultimate "why" question?
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0:20 - 0:22So I'm going to talk about the mystery of existence,
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0:22 - 0:24the puzzle of existence,
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0:24 - 0:27where we are now in addressing it,
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0:27 - 0:29and why you should care,
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0:29 - 0:31and I hope you do care.
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0:31 - 0:34The philosopher Arthur Schopenhauer said that
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0:34 - 0:37those who don't wonder about
the contingency of their existence, -
0:37 - 0:40of the contingency of the world's existence,
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0:40 - 0:42are mentally deficient.
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0:42 - 0:46That's a little harsh, but still. (Laughter)
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0:46 - 0:48So this has been called the most sublime
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0:48 - 0:50and awesome mystery,
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0:50 - 0:53the deepest and most far-reaching question
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0:53 - 0:54man can pose.
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0:54 - 0:55It's obsessed great thinkers.
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0:55 - 0:57Ludwig Wittgenstein, perhaps the greatest
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0:57 - 0:59philosopher of the 20th century,
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0:59 - 1:02was astonished that there should be a world at all.
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1:02 - 1:06He wrote in his "Tractatus," Proposition 4.66,
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1:06 - 1:08"It is not how things are in the world
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1:08 - 1:10that is the mystical,
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1:10 - 1:12it's that the world exists."
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1:12 - 1:14And if you don't like taking your epigrams
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1:14 - 1:17from a philosopher, try a scientist.
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1:17 - 1:20John Archibald Wheeler, one of the great physicists
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1:20 - 1:21of the 20th century,
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1:21 - 1:23the teacher of Richard Feynman,
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1:23 - 1:26the coiner of the term "black hole,"
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1:26 - 1:28he said, "I want to know
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1:28 - 1:30how come the quantum,
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1:30 - 1:33how come the universe, how come existence?"
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1:33 - 1:35And my friend Martin Amis —
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1:35 - 1:38sorry that I'll be doing a lot of
name-dropping in this talk, -
1:38 - 1:39so get used to it —
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1:39 - 1:44my dear friend Martin Amis once said
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1:44 - 1:47that we're about five Einsteins away from answering
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1:47 - 1:49the mystery of where the universe came from.
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1:49 - 1:51And I've no doubt there are five Einsteins
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1:51 - 1:53in the audience tonight.
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1:53 - 1:55Any Einsteins? Show of hands? No? No? No?
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1:55 - 1:56No Einsteins? Okay.
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1:56 - 2:00So this question, why is there
something rather than nothing, -
2:00 - 2:02this sublime question, was posed rather late
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2:02 - 2:05in intellectual history.
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2:05 - 2:07It was towards the end of the 17th century,
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2:07 - 2:10the philosopher Leibniz who asked it,
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2:10 - 2:12a very smart guy, Leibniz,
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2:12 - 2:14who invented the calculus
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2:14 - 2:17independently of Isaac Newton,
at about the same time, -
2:17 - 2:19but for Leibniz, who asked why is
there something rather than nothing, -
2:19 - 2:22this was not a great mystery.
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2:22 - 2:24He either was or pretended to be
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2:24 - 2:27an Orthodox Christian in his metaphysical outlook,
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2:27 - 2:30and he said it's obvious why the world exists:
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2:30 - 2:32because God created it.
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2:32 - 2:35And God created, indeed, out of nothing at all.
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2:35 - 2:37That's how powerful God is.
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2:37 - 2:41He doesn't need any preexisting
materials to fashion a world out of. -
2:41 - 2:43He can make it out of sheer nothingness,
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2:43 - 2:44creation ex nihilo.
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2:44 - 2:45And by the way, this is what
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2:45 - 2:48most Americans today believe.
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2:48 - 2:50There is no mystery of existence for them.
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2:50 - 2:51God made it.
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2:51 - 2:54So let's put this in an equation.
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2:54 - 2:57I don't have any slides so
I'm going to mime my visuals, -
2:57 - 2:58so use your imaginations.
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2:58 - 3:04So it's God + nothing = the world.
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3:04 - 3:07Okay? Now that's the equation.
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3:07 - 3:09And so maybe you don't believe in God.
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3:09 - 3:11Maybe you're a scientific atheist
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3:11 - 3:14or an unscientific atheist,
and you don't believe in God, -
3:14 - 3:15and you're not happy with it.
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3:15 - 3:18By the way, even if we have this equation,
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3:18 - 3:20God + nothing = the world,
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3:20 - 3:22there's already a problem:
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3:22 - 3:25Why does God exist?
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3:25 - 3:27God doesn't exist by logic alone
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3:27 - 3:29unless you believe the ontological argument,
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3:29 - 3:31and I hope you don't, because
it's not a good argument. -
3:31 - 3:34So it's conceivable, if God were to exist,
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3:34 - 3:37he might wonder, I'm eternal, I'm all-powerful,
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3:37 - 3:40but where did I come from?
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3:40 - 3:42(Laughter)
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3:42 - 3:43Whence then am I?
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3:43 - 3:47God speaks in a more formal English.
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3:47 - 3:49(Laughter)
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3:49 - 3:52And so one theory is that God was so bored with
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3:52 - 3:53pondering the puzzle of His own existence
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3:53 - 3:56that He created the world just to distract himself.
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3:56 - 3:58But anyway, let's forget about God.
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3:58 - 4:00Take God out of the equation: We have
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4:00 - 4:03________ + nothing = the world.
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4:03 - 4:05Now, if you're a Buddhist,
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4:05 - 4:07you might want to stop right there,
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4:07 - 4:08because essentially what you've got is
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4:08 - 4:10nothing = the world,
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4:10 - 4:12and by symmetry of identity, that means
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4:12 - 4:14the world = nothing. Okay?
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4:14 - 4:16And to a Buddhist, the world
is just a whole lot of nothing. -
4:16 - 4:19It's just a big cosmic vacuity.
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4:19 - 4:22And we think there's a lot of something out there
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4:22 - 4:25but that's because we're enslaved by our desires.
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4:25 - 4:27If we let our desires melt away,
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4:27 - 4:30we'll see the world for what it truly is,
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4:30 - 4:32a vacuity, nothingness,
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4:32 - 4:34and we'll slip into this happy state of nirvana
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4:34 - 4:36which has been defined as having
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4:36 - 4:39just enough life to enjoy being dead. (Laughter)
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4:39 - 4:41So that's the Buddhist thinking.
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4:41 - 4:45But I'm a Westerner, and I'm still concerned
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4:45 - 4:47with the puzzle of existence, so I've got
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4:47 - 4:48________ + —
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4:48 - 4:51this is going to get serious in a minute, so —
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4:51 - 4:54________ + nothing = the world.
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4:54 - 4:55What are we going to put in that blank?
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4:55 - 4:57Well, how about science?
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4:57 - 5:00Science is our best guide to the nature of reality,
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5:00 - 5:03and the most fundamental science is physics.
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5:03 - 5:06That tells us what naked reality really is,
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5:06 - 5:09that reveals what I call TAUFOTU,
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5:09 - 5:12the True And Ultimate Furniture Of The Universe.
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5:12 - 5:14So maybe physics can fill this blank,
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5:14 - 5:20and indeed, since about the late 1960s or around 1970,
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5:20 - 5:23physicists have purported to give
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5:23 - 5:26a purely scientific explanation of how
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5:26 - 5:29a universe like ours could have popped into existence
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5:29 - 5:31out of sheer nothingness,
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5:31 - 5:34a quantum fluctuation out of the void.
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5:34 - 5:36Stephen Hawking is one of these physicists,
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5:36 - 5:39more recently Alex Vilenkin,
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5:39 - 5:40and the whole thing has been popularized
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5:40 - 5:43by another very fine physicist and friend of mine,
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5:43 - 5:45Lawrence Krauss, who wrote a book called
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5:45 - 5:47"A Universe from Nothing,"
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5:47 - 5:49and Lawrence thinks that he's given —
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5:49 - 5:52he's a militant atheist, by the way,
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5:52 - 5:53so he's gotten God out of the picture.
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5:53 - 5:56The laws of quantum field theory,
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5:56 - 5:57the state-of-the-art physics, can show how
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5:57 - 5:59out of sheer nothingness,
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5:59 - 6:01no space, no time, no matter, nothing,
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6:01 - 6:04a little nugget of false vacuum
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6:04 - 6:06can fluctuate into existence,
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6:06 - 6:08and then, by the miracle of inflation,
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6:08 - 6:11blow up into this huge and variegated cosmos
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6:11 - 6:13we see around us.
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6:13 - 6:17Okay, this is a really ingenious scenario.
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6:17 - 6:20It's very speculative. It's fascinating.
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6:20 - 6:22But I've got a big problem with it,
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6:22 - 6:24and the problem is this:
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6:24 - 6:25It's a pseudo-religious point of view.
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6:25 - 6:27Now, Lawrence thinks he's an atheist,
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6:27 - 6:30but he's still in thrall to a religious worldview.
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6:30 - 6:35He sees physical laws as being like divine commands.
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6:35 - 6:37The laws of quantum field theory for him
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6:37 - 6:39are like fiat lux, "Let there be light."
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6:39 - 6:44The laws have some sort of ontological power or clout
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6:44 - 6:46that they can form the abyss,
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6:46 - 6:48that it's pregnant with being.
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6:48 - 6:51They can call a world into existence out of nothing.
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6:51 - 6:53But that's a very primitive view of what
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6:53 - 6:54a physical law is, right?
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6:54 - 6:57We know that physical laws are actually
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6:57 - 7:00generalized descriptions of patterns and regularities
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7:00 - 7:02in the world.
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7:02 - 7:04They don't exist outside the world.
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7:04 - 7:06They don't have any ontic cloud of their own.
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7:06 - 7:08They can't call a world into existence
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7:08 - 7:09out of nothingness.
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7:09 - 7:11That's a very primitive view
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7:11 - 7:13of what a scientific law is.
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7:13 - 7:15And if you don't believe me on this,
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7:15 - 7:17listen to Stephen Hawking,
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7:17 - 7:21who himself put forward a model of the cosmos
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7:21 - 7:22that was self-contained,
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7:22 - 7:26didn't require any outside cause, any creator,
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7:26 - 7:27and after proposing this,
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7:27 - 7:30Hawking admitted that he was still puzzled.
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7:30 - 7:33He said, this model is just equations.
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7:33 - 7:36What breathes fire into the equations
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7:36 - 7:39and creates a world for them to describe?
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7:39 - 7:40He was puzzled by this,
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7:40 - 7:44so equations themselves can't do the magic,
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7:44 - 7:46can't resolve the puzzle of existence.
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7:46 - 7:49And besides, even if the laws could do that,
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7:49 - 7:51why this set of laws?
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7:51 - 7:53Why quantum field theory that describes
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7:53 - 7:55a universe with a certain number of forces
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7:55 - 7:56and particles and so forth?
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7:56 - 7:58Why not a completely different set of laws?
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7:58 - 8:01There are many, many mathematically
consistent sets of laws. -
8:01 - 8:05Why not no laws at all? Why not sheer nothingness?
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8:05 - 8:07So this is a problem, believe it or not,
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8:07 - 8:10that reflective physicists really think a lot about,
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8:10 - 8:13and at this point they tend to go metaphysical,
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8:13 - 8:15say, well, maybe the set of laws
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8:15 - 8:16that describes our universe,
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8:16 - 8:18it's just one set of laws
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8:18 - 8:20and it describes one part of reality,
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8:20 - 8:23but maybe every consistent set of laws
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8:23 - 8:25describes another part of reality,
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8:25 - 8:29and in fact all possible physical worlds
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8:29 - 8:31really exist, they're all out there.
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8:31 - 8:33We just see a little tiny part of reality
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8:33 - 8:36that's described by the laws of quantum field theory,
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8:36 - 8:38but there are many, many other worlds,
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8:38 - 8:39parts of reality that are described
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8:39 - 8:41by vastly different theories
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8:41 - 8:44that are different from ours in ways we can't imagine,
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8:44 - 8:48that are inconceivably exotic.
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8:48 - 8:50Steven Weinberg, the father
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8:50 - 8:52of the standard model of particle physics,
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8:52 - 8:55has actually flirted with this idea himself,
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8:55 - 8:59that all possible realities actually exist.
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8:59 - 9:02Also, a younger physicist, Max Tegmark,
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9:02 - 9:07who believes that all mathematical structures exist,
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9:07 - 9:09and mathematical existence is the same thing
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9:09 - 9:11as physical existence,
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9:11 - 9:13so we have this vastly rich multiverse
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9:13 - 9:16that encompasses every logical possibility.
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9:16 - 9:20Now, in taking this metaphysical way out,
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9:20 - 9:22these physicists and also philosophers are actually
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9:22 - 9:25reaching back to a very old idea
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9:25 - 9:26that goes back to Plato.
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9:26 - 9:29It's the principle of plenitude or fecundity,
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9:29 - 9:31or the great chain of being,
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9:31 - 9:35that reality is actually as full as possible.
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9:35 - 9:37It's as far removed from nothingness
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9:37 - 9:40as it could possibly be.
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9:40 - 9:42So we have these two extremes now.
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9:42 - 9:45We have sheer nothingness on one side,
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9:45 - 9:48and we have this vision of a reality
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9:48 - 9:51that encompasses every conceivable world
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9:51 - 9:54at the other extreme: the fullest possible reality,
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9:54 - 9:57nothingness, the simplest possible reality.
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9:57 - 10:00Now what's in between these two extremes?
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10:00 - 10:02There are all kinds of intermediate realities
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10:02 - 10:05that include some things and leave out others.
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10:05 - 10:06So one of these intermediate realities
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10:06 - 10:12is, say, the most mathematically elegant reality,
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10:12 - 10:14that leaves out the inelegant bits,
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10:14 - 10:16the ugly asymmetries and so forth.
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10:16 - 10:19Now, there are some physicists who will tell you
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10:19 - 10:22that we're actually living in the most elegant reality.
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10:22 - 10:25I think that Brian Greene is in the audience,
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10:25 - 10:29and he has written a book
called "The Elegant Universe." -
10:29 - 10:31He claims that the universe we live in mathematically
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10:31 - 10:33is very elegant.
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10:33 - 10:34Don't believe him. (Laughter)
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10:34 - 10:38It's a pious hope, I wish it were true,
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10:38 - 10:39but I think the other day he admitted to me
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10:39 - 10:43it's really an ugly universe.
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10:43 - 10:44It's stupidly constructed,
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10:44 - 10:47it's got way too many arbitrary coupling constants
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10:47 - 10:49and mass ratios
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10:49 - 10:52and superfluous families of elementary particles,
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10:52 - 10:54and what the hell is dark energy?
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10:54 - 10:57It's a stick and bubble gum contraption.
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10:57 - 11:01It's not an elegant universe. (Laughter)
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11:01 - 11:04And then there's the best of all possible worlds
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11:04 - 11:05in an ethical sense.
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11:05 - 11:07You should get solemn now,
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11:07 - 11:10because a world in which sentient beings
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11:10 - 11:11don't suffer needlessly,
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11:11 - 11:13in which there aren't things like
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11:13 - 11:16childhood cancer or the Holocaust.
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11:16 - 11:17This is an ethical conception.
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11:17 - 11:19Anyway, so between nothingness
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11:19 - 11:20and the fullest possible reality,
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11:20 - 11:22various special realities.
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11:22 - 11:24Nothingness is special. It's the simplest.
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11:24 - 11:28Then there's the most elegant possible reality.
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11:28 - 11:29That's special.
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11:29 - 11:32The fullest possible reality, that's special.
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11:32 - 11:33But what are we leaving out here?
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11:33 - 11:36There's also just the crummy,
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11:36 - 11:38generic realities
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11:38 - 11:40that aren't special in any way,
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11:40 - 11:42that are sort of random.
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11:42 - 11:45They're infinitely removed from nothingness,
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11:45 - 11:49but they fall infinitely short of complete fullness.
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11:49 - 11:51They're a mixture of chaos and order,
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11:51 - 11:55of mathematical elegance and ugliness.
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11:55 - 11:57So I would describe these realities
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11:57 - 12:01as an infinite, mediocre, incomplete mess,
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12:01 - 12:05a generic reality, a kind of cosmic junk shot.
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12:05 - 12:07And these realities,
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12:07 - 12:09is there a deity in any of these realities?
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12:09 - 12:12Maybe, but the deity isn't perfect
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12:12 - 12:14like the Judeo-Christian deity.
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12:14 - 12:17The deity isn't all-good and all-powerful.
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12:17 - 12:21It might be instead 100 percent malevolent
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12:21 - 12:23but only 80 percent effective,
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12:23 - 12:29which pretty much describes the world
we see around us, I think. (Laughter) -
12:29 - 12:31So I would like to propose that the resolution
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12:31 - 12:33to the mystery of existence
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12:33 - 12:37is that the reality we exist in
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12:37 - 12:39is one of these generic realities.
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12:39 - 12:42Reality has to turn out some way.
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12:42 - 12:44It can either turn out to be nothing
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12:44 - 12:48or everything or something in between.
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12:48 - 12:52So if it has some special feature,
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12:52 - 12:54like being really elegant or really full
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12:54 - 12:55or really simple, like nothingness,
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12:55 - 12:57that would require an explanation.
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12:57 - 13:00But if it's just one of these random, generic realities,
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13:00 - 13:02there's no further explanation for it.
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13:02 - 13:04And indeed, I would say
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13:04 - 13:06that's the reality we live in.
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13:06 - 13:08That's what science is telling us.
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13:08 - 13:09At the beginning of the week,
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13:09 - 13:13we got the exciting information that
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13:13 - 13:16the theory of inflation, which predicts a big,
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13:16 - 13:20infinite, messy, arbitrary, pointless reality,
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13:20 - 13:23it's like a big frothing champagne
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13:23 - 13:26coming out of a bottle endlessly,
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13:26 - 13:28a vast universe, mostly a wasteland
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13:28 - 13:33with little pockets of charm and order and peace,
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13:33 - 13:35this has been confirmed,
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13:35 - 13:38this inflationary scenario, by the observations
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13:38 - 13:40made by radio telescopes in Antarctica
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13:40 - 13:43that looked at the signature of the gravitational waves
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13:43 - 13:45from just before the Big Bang.
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13:45 - 13:46I'm sure you all know about this.
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13:46 - 13:49So anyway, I think there's some evidence
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13:49 - 13:53that this really is the reality that we're stuck with.
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13:53 - 13:56Now, why should you care?
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13:56 - 13:57Well — (Laughter) —
-
13:57 - 14:01the question, "Why does the world exist?"
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14:01 - 14:02that's the cosmic question, it sort of rhymes
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14:02 - 14:04with a more intimate question:
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14:04 - 14:07Why do I exist? Why do you exist?
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14:07 - 14:10you know, our existence would
seem to be amazingly improbable, -
14:10 - 14:15because there's an enormous number
of genetically possible humans, -
14:15 - 14:16if you can compute it by looking at
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14:16 - 14:18the number of the genes and the
number of alleles and so forth, -
14:18 - 14:21and a back-of-the-envelope calculation will tell you
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14:21 - 14:23there are about 10 to the 10,000th
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14:23 - 14:25possible humans, genetically.
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14:25 - 14:28That's between a googol and a googolplex.
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14:28 - 14:30And the number of the actual
humans that have existed -
14:30 - 14:32is 100 billion, maybe 50 billion,
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14:32 - 14:34an infinitesimal fraction, so all of us,
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14:34 - 14:36we've won this amazing cosmic lottery.
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14:36 - 14:38We're here. Okay.
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14:38 - 14:41So what kind of reality do we want to live in?
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14:41 - 14:43Do we want to live in a special reality?
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14:43 - 14:48What if we were living in the
most elegant possible reality? -
14:48 - 14:50Imagine the existential pressure on us
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14:50 - 14:52to live up to that, to be elegant,
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14:52 - 14:54not to pull down the tone of it.
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14:54 - 14:57Or, what if we were living
in the fullest possible reality? -
14:57 - 14:59Well then our existence would be guaranteed,
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14:59 - 15:01because every possible thing
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15:01 - 15:02exists in that reality,
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15:02 - 15:04but our choices would be meaningless.
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15:04 - 15:07If I really struggle morally and agonize
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15:07 - 15:09and I decide to do the right thing,
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15:09 - 15:11what difference does it make,
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15:11 - 15:13because there are an infinite number
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15:13 - 15:14of versions of me
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15:14 - 15:15also doing the right thing
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15:15 - 15:17and an infinite number doing the wrong thing.
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15:17 - 15:18So my choices are meaningless.
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15:18 - 15:21So we don't want to live in that special reality.
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15:21 - 15:23And as for the special reality of nothingness,
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15:23 - 15:26we wouldn't be having this conversation.
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15:26 - 15:32So I think living in a generic reality that's mediocre,
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15:32 - 15:34there are nasty bits and nice bits
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15:34 - 15:36and we could make the nice bits bigger
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15:36 - 15:38and the nasty bits smaller
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15:38 - 15:41and that gives us a kind of purpose in life.
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15:41 - 15:43The universe is absurd,
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15:43 - 15:44but we can still construct a purpose,
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15:44 - 15:45and that's a pretty good one,
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15:45 - 15:48and the overall mediocrity of reality
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15:48 - 15:50kind of resonates nicely with the mediocrity
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15:50 - 15:53we all feel in the core of our being.
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15:53 - 15:54And I know you feel it.
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15:54 - 15:56I know you're all special,
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15:56 - 15:58but you're still kind of secretly mediocre,
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15:58 - 15:59don't you think?
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15:59 - 16:01(Laughter) (Applause)
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16:01 - 16:05So anyway, you may say, this
puzzle, the mystery of existence, -
16:05 - 16:07it's just silly mystery-mongering.
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16:07 - 16:11You're not astonished at the existence of the universe
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16:11 - 16:12and you're in good company.
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16:12 - 16:14Bertrand Russell said,
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16:14 - 16:18"I should say the universe is just there, and that's all."
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16:18 - 16:19Just a brute fact.
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16:19 - 16:22And my professor at Columbia, Sidney Morgenbesser,
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16:22 - 16:24a great philosophical wag,
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16:24 - 16:26when I said to him, "Professor Morgenbesser,
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16:26 - 16:28why is there something rather than nothing?"
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16:28 - 16:30And he said, "Oh, even if there was nothing,
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16:30 - 16:32you still wouldn't be satisfied."
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16:32 - 16:36So — (Laughter) — okay.
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16:36 - 16:38So you're not astonished. I don't care.
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16:38 - 16:41But I will tell you something to conclude
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16:41 - 16:44that I guarantee you will astonish you,
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16:44 - 16:46because it's astonished all of the brilliant,
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16:46 - 16:49wonderful people I've met at this TED conference,
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16:49 - 16:51when I've told them, and it's this:
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16:51 - 16:55Never in my life have I had a cell phone.
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16:55 - 16:57Thank you.
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16:57 - 17:01(Laughter) (Applause)
- Title:
- Why does the universe exist?
- Speaker:
- Jim Holt
- Description:
-
Why is there something instead of nothing? In other words: Why does the universe exist (and why are we in it)? Philosopher and writer Jim Holt follows this question toward three possible answers. Or four. Or none.
- Video Language:
- English
- Team:
- closed TED
- Project:
- TEDTalks
- Duration:
- 17:17
Morton Bast edited English subtitles for Why does the universe exist? | ||
Morton Bast approved English subtitles for Why does the universe exist? | ||
Morton Bast edited English subtitles for Why does the universe exist? | ||
Morton Bast edited English subtitles for Why does the universe exist? | ||
Morton Bast edited English subtitles for Why does the universe exist? | ||
Madeleine Aronson accepted English subtitles for Why does the universe exist? | ||
Madeleine Aronson edited English subtitles for Why does the universe exist? | ||
Madeleine Aronson edited English subtitles for Why does the universe exist? |