[Weinberg] expli- it's a little bit like the
explanations the uh, the Greeks were
satisfied. You know, Aristotle explained
falling bodies by saying they're going
to their natural place, which is toward
the center of the earth. Well, when
you say that, you really haven't 
learned anything more about
falling bodies; it hasn't helped you
to say that. And in the same way, talking
about a god who is comp- complex
and has created the world the way it is,
you haven't learned anything. It 
doesn't help you to anticipate anything
[Weinberg] you'll discover in nature. 
[Dawkins] (muffled) That's right...
[Weinberg] But I don't think one should underestimate, 
uh, the fix we're in. That in the end, we will
not be able to explain, uh, the world. 
That uh, we will have some laws of- some
set of laws of nature; we will not be 
able to derive them on the grounds
simply of mathematical consistency, 
because we can already think of
mathematically consistent laws that don't 
describe the world as we know it, and
we will always be left with a uh, question:
why are the laws of nature what they are
rather than some other laws. And uh, I
don't see any way out of that, and I-
I just regard it as just another one of 
the tragedies that we have to get used
to, like the tragedy that we will die, and
the tragedy- well, I don't want to, uh, linger
on tragedy, but I think that essentially 
the position of human beings is a
tragic one, uh, and the more we
understand, the more clearly tragic it is.
And um, part of it, which particularly affects
a physicist, is the tragedy of never
being able to come to a really satisfying conclusion 
(rolling thunder)
of our questions why, and uh, per-
you know, what do we do in this
tragedy? I think, uh... well Shakespeare
showed us that one way of live with
[Weinberg] tragedy is to mix it in with comedy-
[Dawkins] Yes, yeah.
[Weinberg] And um, uh, we can have- we can
take a certain amusement that our
position, always seeking why, why, why,
never coming to the end.
Um, I think humor is one of the 
leavening agents that uh, makes our-
the tragedy of position possible. Uh...
the Greeks, in writing their plays,
didn't understand that, that you could 
mix comedy and tragedy.
[Dawkins] Yeah.
[Weinberg] There's no comedy in Sophocles.
Um, but Shakespeare understood and I think that's
[Weinberg] what's so great about Shakespeare
[Dawkins] I think that's right. I mean moving
to another level, I love the comic 
novels of Douglas Adams. Uh, have
[Dawkins] you read any of his, Hitchhiker's-
[Weinberg] No, no, no...
[Weinberg] Oh, well, I think you might like them,
because he uses comedy, but in a
rather sophisticated scientific way, 
and so his jokes would really appeal
to a- a modern physicist who 
understands-
[Weinberg] Well I've heard of the one, you know,
"what is the secret to everything?"
[Weinberg] It's 43 or some-
[Dawkins] No, no, yeah, they've- they've much better
[Dawkins] than that, but I can't think of any off hand-
[Weinberg] Oh I see. But I've never read any, no.
[Dawkins] You might- you might enjoy it. But 
going back to the tragedy of never
finally understanding, I mean
you're making pretty good progress
working your way back through the 
first three minutes, and- and getting
[Weinberg] Mm, yeah.
[Dawkins]...where are you now? To the first
[Dawkins] picosecond or- or something?
[Weinberg] Oh it's- it's... I- we don't- I mean
if our present... there's so many powers
of ten that I don't even know what
[Weinberg] English word to apply to it, but...
[Dawkins] Yes.
[Weinberg] Uh, we certainly... uh, can directly 
observe the universe as it was when
it was 380,000 years old. That's the
microwave radiation that comes to us
essentially undisturbed from that time,
and that's been- it's a great success
story in cosmology. The detailed analysis
of this radiation that fills the universe
and is not quite uniform everywhere;
it's the nonuniformities that are so
[Weinberg] interesting. Um...
[Dawkins] And so important for what happened later
[Dawkins] of course, yes?
[Weinberg] Yes, well they- that- they are the
nonuniformities that ultimately grew into
uh, the protogalaxies, and then galaxies,
and then clusters of galaxies, 
and uh, allowed us to arise.
Um, but looking back earlier than the
first 380,000 years old, we- we have
theories, and the theories work. In fact,
uh, some of our theories that describe
what happened when the universe was 
three minutes old tell us the chemical
composition with which the stars started.
And that works too; I mean the
predictions come out right. Uh, there's a
certain amount of hydrogen, a certain amount
of helium, a certain amount of certain
rare isotopes of hydrogen and helium;
helium-3 and hydrogen-2, that uh, we can
calculate the amounts, and that's what we
observe in the oldest stars. So that, 
actually, more accurately, that's what we
observe in uh, the intergalactic material
out of which the stars form.
Uh, so in terms of things we can actually 
observe, I suppose you could say we've
traced the history of the universe back to
the first three minutes. Uh, earlier than
that it's just pure theory. Except that...
the- these in- nonuniformities in the
microwave radiation which are so
important, which we're studying with radio
telescopes, and with which we believe, and
have every reason to believe, grew into
the distribution of matter we see in the sky.
These, nonuniformities, we believe we
have a theory for their origin. In terms
of a "pre-big bang" phase called the
period of inflation, and it works. 
That is, it predicts certain properties,
for example, the- the strength of the
fluctuations as a function of how
large they are. Um, what's the probability
of seeing a fluctuation this big as
compared to one that big. Uh, that theory
works, and it deals with a period of time
which is incredibly early in the history 
of the universe. So much- so early that
you really begin to wonder whether there
really was a beginning or should you
even talk about a beginning. I mean, it's
so... I don't even know how to say how
early it is, but it- it's way earlier than
the first hundr- 380,000 years or the
first three minutes; it's uh, it's an 
incredibly small fraction of a second
after the beginning. And those theories
seem to work. But you know, that's
only going back so far. Then you have to 
go back to what started inflation, what
started this inflationary period? And we 
have theories, there are some attractive
theories, but they can't be tested. We
don't have any observational handle
[Weinberg] on them.
[Dawkins] Even without an observational handle,
[Dawkins] however, if you've got a theory which is
even plausible, I'd be grateful for that.
[Weinberg] Well there is the theory of chaotic
cos- uh, inflation, due to Andre Linde
at Stanford, that um, there are certain 
fields, uh, they're the kind of fields
we encounter in our modern theories
of elementary particle physics; they're
known technically as scalar fields, that
fill the universe, and essentially,
th-they are chaotic at the beginning.
One does not impose any particular
initial condition on the universe. Uh, 
it's just as complicated as you can imagine.
Which is a nice beginning because you
don't have to fine tune any initial conditions.
And uh, this burbles on and i- i- it- 
you have fluctuations which are continually
increasing and decreasing, it's all very 
complicated. Every once in a while,
sheerly by accident, a patch of this 
fluctuating field becomes- happens to
become smooth, that is, it- it doesn't 
vary much over a sufficiently large
region of space. Just by accident. Not by 
any design. That region, you can show,
according to reasonable dynamical 
assumptions, will then blow up
will inflate, will increase in size
exponentially, becoming smoother
and smoother, turning into the inflationary
phase, which we think preceded our
big bang. But this didn't just happen once,
it happened again and again, and perhaps
time without end. And uh, our big bang,
that we are- that is all that we can observe
directly, that is 13.7 billion years old,
and we now know that number to
[Weinberg] one percent...
[Dawkins] Right.
[Weinberg] Uh, that big bang is just one episode in 
a chaotic universe which is always
[Weinberg] burping off these big bangs-
[Dawkins] So does- does that mean there are lots
[Dawkins] of universes, the?
[Weinberg] There are- well, what we call a universe,
[Weinberg] our big bang, there are lots of them. 
I mean, pres- I guess for linguistic
purity, when one should reserve the word 
universe for the whole thing-
[Dawkins] For a- for- yes, okay.
[Weinberg]...for the whole shebang.
