[♪♪♪] [♪♪♪] ROBERT LAWRENCE KUHN:<i>
How does the world work
at its most fundamental?</i> <i> Can we human beings
penetrate</i> <i> the deepest secrets
of the world?</i> <i>What does most fundamental mean?</i> <i> It means one can
look no further.</i> <i>It means it is impossible, even
in principle, to go further.</i> <i> It means explanatory bedrock.</i> <i> What's down there?</i> <i>The laws of fundamental physics,
quantum mechanics,</i> <i> perhaps string theory
below that,</i> <i> perhaps a final theory
of everything,</i> <i> the holy grail of science.</i> <i> I see a challenge to this
model of how the world works.</i> <i> It's called Strong Emergence.</i> <i> And it claims that each level
of the hierarchy of the sciences</i> <i> from physics to chemistry
to biology to psychology</i> <i> has its own special laws.</i> <i> Is Strong Emergence
a deep secret mechanism</i> <i> by which the world
conducts its business?</i> <i> What would Strong Emergence
mean?</i> <i> I'm Robert Lawrence Kuhn
and Closer to Truth</i> <i> is my journey to find out.</i> [♪♪♪] <i> How can Strong Emergence
make such a startling claim?</i> <i> That those special laws
in the various sciences,</i> <i>particularly in biology, cannot
be completely reduced to</i> <i> or fully explained by physics.</i> <i> Not even by that final
theory of everything.</i> <i> To discern Strong Emergence,
is it real?</i> <i> How could it work?</i> <i> I've been looking to meet one
of its leading proponents,</i> <i>the distinguished mathematician,
and cosmologist, George Ellis.</i> <i> George lives in South Africa.</i> <i> So, when I hear he's attending
a conference in Crete,</i> <i> I also make plans to attend.</i> <i>As mesmerizing seascapes emerge</i> <i> at the interface
of sea and shore,</i> <i> I wonder is emergence
mere metaphor.</i> <i> I'd spoken with George Ellis
years before.</i> <i> Now I'm ready to talk
Strong Emergence.</i> George, the claim that has
been growing is that in order to explain
how everything works, you need this concept
of emergence. Okay. Well, let's ask
the following question. If we knew everything about what
was the state of the universe at the time
of the last scattering of the cosmic microwave
background of matter. Which is basically
14 billion years ago, could you predict
what you and I are saying to each other today
from that data? Some of the strong physicalists
believe that, that would be the case and I think it's
absolutely clear that there it isn't remotely possible
this would be the case, because the fluctuations on the
surface of the last scattering, if you believe
standard cosmology or random Garcia fluctuation. Now, out of that, emergence
has taken place over time of animals, of human beings
are able to think. And human beings then can
discuss and produce books like Einstein's<i>
Theory of Relativity,</i> Darwin's book on the origin
of the species, okay. Now, those books contain
logical argumentation. There is no way that logical
argumentation was implied in any sense by that data on the cosmic microwave
background surface. Something has happened between
there and there which has led to that
logical argumentation appearing in the real world which
it has undoubtedly has done. On its surface, that's correct. But what I could do is I can
throw in an evolutionary picture and then it would develop the
nervous system and the brain. And then you have interactions
between brains and communities
and I can give a story. Yes, but the physics does not
come into that story, in any way, except facilitating
what, what -- you're bringing in
a Darwinian picture. No physics book has got Darwin's
law as a law of physics. Sure. Sure. No physics books has got a law,
has got the Hodgkin Huxley equations as
a law of physics. They are imagined. But those rules or laws
or understandings came out of a mechanism of the brain
that somebody came up with. And in some ultimate analytical
sense, you could describe how those ideas came, in terms of
something in the physical world. Unless the claim is that at
some levels, there is something that is absolutely non-reducible
to the physical. The claim is that through some
of the processes you indicated, many of which are not physical, although they're allowed
by the physics. Brains came into being
which are able to carry out logical argumentation
as an argumentation at the psychological level. And that argumentation is
what leads to, for instance, E to the I pie plus one
is equal to zero being written down
on a piece of paper. The physics knows absolutely
nothing about that. You have to have the emergence
of the possibility of logical argumentation
to take place. That logical argumentation
then has the possibility of controlling what
appears on the piece-- So, so, okay. But you're not requiring
anything of a non-physical nature here at this point,
or are you? I am.
An idea is a non-physical thing. An idea is realized
in the brain but the idea itself
is not a physical thing. Okay. Now everything we see around us
here, basically, except for the trees was designed
by the human mind. So, the mind is coarsely
effective and thoughts are coarsely effective but a
thought is not a physical thing. It's realized
in a physical way but it is not of itself
a physical thing. The idea exists
and it has its own validity but it is only realized because of the physical things
going on below? I mean,
if there's nothing else. Unless you're saying that
the laws of physics, when they get to a certain
level, create thing that in principle can never
be understood by the microphysics laws. Well, it can't be understood. You can't understand E to the I
pie plus one is equal to zero in terms of maxual decrays
[ph] and interacting electrons. I think that's pretty obvious. You can't understand it
at that level. You can't understand that
at that level, that's right. But ultimately, that's the only
way it's realized in terms of-- No, no. That's just the way
it's realized, yes. So, you've got multiple levels. You've got
the atomic level. You've got the molecular level,
you've got the systems level. All of these are simultaneously
causations taking place simultaneously, and all of them,
in such a way, that the logical thing
can be worked out. But it's the logic which
is driving what happens. It's the physics which
enables it to happen but the logic is deciding
the outcome. So, you have what would
be downward causation? - Downward realization.
- Downward realization. So, what's the difference
between causation and realization? You didn't
like my word causation? I've been persuaded recently,
different from what I've written about before, that
causation is always horizontal. Emergence is vertical,
and realization is downwards. Oh, yeah. That, that I can,
I can understand that. I'm just trying to think
this out, get me wherever
you want to get me. Well, what is useful as
a computer is an analog and when a computer, for
instance, sorts a list of names, you feed in a program
at the top and an algorithm is changed down through
a series of virtual machines to the bottom level,
by compilers and interpreters. And that's the machine
language at the bottom. The machine language does it
and then it goes up again and what you fed in at the top,
results in the list being printed out. The electrons flowing the gates
enable it to happen but it's the algorithm
which has decided what will, in fact, happen. But the algorithm is
represented ultimately in terms of the transistors
and... Correct. And at this level,
it's the laws of -- it's Maxwell's equations,
and Newton's equations at this level.
But at this level, it is the logic of the algorithm
which is deciding what will happen at that level
and ultimately, it's that which decides which
electrons will flow through which gates at the bottom level. It's the top level decides
what will be done and the lower levels
carry out the work. So, let me ask this question. We know the H2O is water. If I gave you some
gas of hydrogen, gas of oxygen and
hydrogen, could you ever predict that if you got a lot of it
together, it would be wet? No. The answer is no,
you can't. This is one of
the problems with-- Okay. So, I think there are
people who say that you can. Well, alright. Let me, let me-- Because you -- when you
know that the angle between the hydrogen
and the oxygen, then you can put a lot together,
you can see how they would slip, and how wetness could occur. There is a great problem
in deriving the macro properties of waters from
the micro properties. But let me make
the following statement. By the time you've done that,
the hydrogen atom no longer exists
as a hydrogen atom. It only exists as
a water molecule. So, the lower level
no longer exists as the individual entities. They've got incorporated
at a higher-level interchange. Okay. But if you knew
everything about the hydrogen and the oxygen
you should be able to predict the wetness of water
if you have it in groups? You should. In the case of
water, in principle, absolutely. You can do that. So, the question is,
is the water example different than your other examples? Absolutely, because
in the other cases, there's logical stuff
going on at that level -- well, let me go back
to that computer example. Exactly the same logic
gets re-written at each of those levels. It gets written in Fortran,
it gets re-written in Java. It's written in Assembly. Gets re-written
in machine language. And then, it gets incorporated
into physical systems. The logic is still the thing
that is driving everything. And the logic does get embodied
in the lower level structures, they are realizing it, but
the thing that is driving it is an abstract entity
of the logic. KUHN:<i> This is Strong Emergence
in its full-throated defense.</i> <i> George is its apostle.</i> <i> And I learned to distinguish
Strong Emergence</i> <i> from Simple or Weak Emergence.</i> <i> The latter is the idea that
radically different properties</i> <i> in science, can,
with deeper knowledge</i> <i> of the underlying physics,
be explained,</i> <i> like the wetness of water.</i> <i> Everyone signs on to
Simple or Weak Emergence.</i> <i> It's not controversial.</i> <i> But Strong Emergence
would be an astonishing thing.</i> <i> Utterly transformative.</i> <i> A new radical way
of how the world works.</i> <i> Could human logic,</i> <i> at the highest macro level
in our minds,</i> <i>drive the physics at the lowest
micro level in our brains?</i> <i> Even though human logic itself
is composed of nothing</i> <i> but that same microphysics
in our brains.</i> <i>It sounds circular, mysterious,
yet I'd be hard pressed</i> <i> to name a more axial question
in the physical world.</i> <i> That's why I subject Strong
Emergence to strong critique</i> <i> and here at the
Crete conference,</i> <i> I have no trouble
finding strong critics.</i> <i> I begin with a philosopher
of science,</i> <i> an expert on the foundations
of physics, David Albert.</i> David, you talk about the laws
of physics being such that, that is all the science that you
need in an ultimate sense. Now, that is directly
contradictory to what I perceive as a growing interest in
the concept of emergence, in what's so-called
the strong way, which means to me
that in principle, you can't explain
certain things that happen based on reductionism
to physics. Right. First of all, I don't at
all want to be in the position of claiming that I know
what the answer is here. I don't. What I do feel strongly is that,
you know, reports of the demise of the possibility of reducing
everything to physics have again and again
and again been greatly and hyperbolically exaggerated in discussions of
the foundations of physics. I think that the idea of the
possibility of producing a sort of fundamental mechanical
explanation of everything is in all sorts of ways,
terrifying, okay. That in some deep sense there
isn't an important distinction between us and rocks. But we have this
physical project that started out by trying
to explain rocks. And was this unbelievable
fantastic success, applying the same methods
again and again and again to more and more
complicated systems. So, to the extent, that I have
a position on this, it's not a position on how
it ought to come out, okay. It's a position on what the most
interesting course to pursue through this is. And yes, I think that a sort
of idea that the world can potentially be reduced to a
set of fundamental mechanical phenomena in order to defend
the sanctity of human life or something like that, the
specialness of consciousness, the death of this project
has been announced. And those announcements
have always turned out to be premature. Now when you're using the word
mechanical you mean, I mean, in all the sophistication of-- In all the sophistication,
but I mean, once upon a time, quantum mechanics was thought to
be fundamentally incompatible with claims that there's
a real world out there that can be described
in full detail. I would say the most prominent
of the premature announcements of the death of mechanical
explanations in the world was what accompanied
the development of quantum mechanics. We had figures like Borg
and Heisenberg and so on, who were announcing the death
of attempts to understand the world
deterministically. One of the few prominent voices
resisting this, at the time, was Einstein, who by the time of
his death, was widely considered to have sort of lost touch with the latest developments
in physics. Nowadays, after another 50 or
60 years of reflection on this, most serious investigators
of the foundations of quantum mechanics think
that it was Einstein who won that argument
and not Borg. And the kinds of demands
that Einstein was making for a realistic account of the
world, for a mechanistic account of the world, turn out to
be much more possible, even in the context
of quantum mechanics. Let me tell you a problem
I have in understanding. There are a host of really top
scientists who are non-theistic - and in fact, non-dualistic.
- Right. They believe only in
the physical world. But yet, are committed
to the concept - of so-called Strong Emergence.
- Yes. Which means that, in principle
it is impossible forever to be able to explain
certain laws or activities that at higher levels
of biology, or chemistry or society or whatever. In
terms of the fundamental. What would be a law,
at a higher level, that only could say,
they have the constraints, only composed
of the physics? And yet, it's impossible
in principle to predict it. I don't understand
how that could work. Look, I have to play devil's
advocate here because I'm puzzled about how that
could be believed, as well. There are all kinds
of arguments. This is an argument due to
a very well-known philosopher named Jerry Fodor. Jerry says look,
take a law of economics, transfers of money
of various kinds have such and such
economic effects. Jerry says look,
transfers of money take very different
physical forms. Sometimes there are changes
in location of pieces of paper. Other times they are electronic
events in bank computers. These things have absolutely
nothing physical in common with one another. But it's true of every one
of them that they increase inflation
or something like that. How could that possibly be
a physical law? Or follow from physical laws
because these events only have something in common when
looked at the economic level. They have nothing at all
in common when looked at, at the physical level. No, I understand that and,
but what that means to me is that you then have to encode
all of those factors, neural activity, and then
those neural activity. It's enormous and complicated,
for sure. It's just an encoding problem. I agree with that.
I think this is just a mistake. Yes, it turns out that there
are a whole bunch of very physically different
kinds of situations which, none the less,
once you read it economically, in the same economic direction,
I think that's what's going on. Now, there are deeper
problems about this. There are problems,
especially with consciousness, that talking about consciousness
as just the motion of these ions in your brain,
it just strikes people as apples and oranges, okay. And I think there are
very deep mysteries there. Maybe the project
of reductive physicalism will succeed
or maybe it will fail. This is this powerful, weird,
creepy idea, okay that has made a place for itself in human
discourse about the world. For my money, the interesting
thing to do with it, is drive it as hard as you can. KUHN:<i> Dave cannot imagine
how Strong Emergence</i> <i> could drive the underlying
physics which composes</i> <i> whatever generates Strong
Emergence in the first place.</i> <i> I can't either.</i> <i> Though I, as Dave,
would not find happiness</i> <i> in a purely physicalist
materialist world.</i> <i> Any possibility of
transcendence, God,</i> <i>life after death, deep purpose,
all out the window.</i> <i> Rejecting Strong Emergence
seems sensible science.</i> <i> But George Ellis
alone gives me pause.</i> <i> Could Strong Emergence
be a philosophical problem?</i> <i> I ask a philosopher of science
who focuses on big questions</i> <i> of cosmology and mind,
Barry Loewer.</i> Barry, the question, do you
need anything but physics? Chemistry, biology, psychology. Is there any laws at that level
which are so strongly emergent that they are not predictable by
the underlying laws of physics? Well, I think it's important
to distinguish two kinds of questions, what we might
call ontological or metaphysical questions
on the one hand, and epistemological
questions on the other. If you mean that somebody who
was told like Laplace's famous example of the demon who is
told the positions and momentum of every particle
in the universe, whether the demon could predict
all of the regularities found in psychology and so on, I think the answer to that is
that the demon could predict where, for example,
there would be living beings. And where not living beings. Where there would be volcanoes
and where there would be oceans, and so on. But I don't think human
beings could do that. The predictions are way, way
too complicated. And there are some conceptual
issues that get in the way too. So, our macroscopic descriptions
are inevitably vague. So, the epistemological question
is could we actually do biology by just doing physics
and the answer is no. On the other hand,
the metaphysical question: Are there regularities or laws
of biology which are determined to be what they are from
the fundamental physics? I think the answer to that is
also no, with a qualification. The qualification is this, that
physics is usually described in terms of the fundamental
dynamical laws of physics. But I think that something more
than the fundamental dynamical laws of physics are part of
physics, that will be needed in order to even understand how
the higher-level regularities fit into the lower level
physics. Because the higher-level
regularities are generally probabilistic. As I think what one needs,
in addition, to the fundamental dynamical laws of physics, also
what is sometimes thought of as the laws of
statistical mechanics. By that, I don't mean
the macroscopic laws of statistical mechanics like
the second law of entropy. I mean, what Boltzmann
introduced to explain the laws of thermodynamics, namely a probability
distribution over all the microstates
of the universe. And the idea that the state
of the universe and very early, what we call
early times, at the time of the Big Bang,
had very, very tiny entropy. I do think that the package
of the low entropy, the probability distribution,
and the correct dynamical laws, I think them together,
are sufficient to, in principle, in Laplace's story
get the patterns and regularities of
the higher-level stories. Okay. But,
at the end of the day, you're saying that
all of the regularities, the special kinds,
and relationships in biology can ultimately in principle,
you can be able to do that? Because Strong
Emergence says you can't. That's right. Strong Emergence says there's
something that happens, in some sense,
in the physical world, that as you go up a level, the laws of physics at the
lowest levels will, in principle, not be able
to make that jump to that level of biology. That is right. I think
that the weight of reason is on the side of
they can make the jump. And here's the reason
I'm saying that. That if the jump
couldn't be made, then there must be some ways
in which the microphysical world evolves, which can't be accounted
for in terms of microphysics. And the reason for that is that
any change in the world at a macroscopic level,
let's say that involved biology or psychology, could itself make
for a change at the micro level. Because it could be registered
in a computer, for example. And so, somebody who took the
view of there being this kind of Strong Emergence, would
also be taking the view that microphysics is
of its nature, incompletable. Now that is a view
that people have had. For example, Descartes. Descartes held the view that
the motions of human bodies, particularly the motions of our
bodies when we produce language, cannot be accounted for
just in a mechanical means. Now, he didn't know at all,
the right mechanical means or the right fundamental
physical theory. But, even in principle,
he thought it couldn't be done because they thought that
this could only be explained in terms of mentality. I do think there
are explanations in terms of mentality
but I also think that there are explanations in
terms of fundamental physics, of why things happen
the way they happen. So, there's a kind of
over explanation. I don't think of this
as over determination because I don't think of the
prior state or situation as, in a fundamental way,
determining the later one, in a sense though causation was
something that's fundamental. For those people who think of
causation as something that's fundamental, like a
fluid which has to be given from one thing to another thing,
they might get worried, that look how it could be that there's a physics
causal explanation? And also, a psychological
causal explanation because there's just too much
of this causal fluid. And that seems a bit silly. KUHN:
That's the overdetermination. I just don't think of causation
like that at all. I think if causation as just
evolving truths like -- look, if the psychological event
hadn't occurred, then the physical event
wouldn't have occurred. So, if you hadn't thought
about elephants, you wouldn't have waved
your hand like that. And there's also
a physical counterfactual. If such and such had not gone on
in your brain, you wouldn't have waved
your hand like that. And these are perfectly
compatible with each other. KUHN:<i> The challenge of
Strong Emergence, to me,</i> <i> is a deep probe
of how the world works.</i> <i> Strong Emergence
is stark and controversial.</i> <i>Laws, regularities, properties,
that can never be explained</i> <i> by the underlying physics
seems mystifying.</i> <i> Never, not because processes
are too complex to know them,</i> <i> but never because
we cannot ever know them.</i> <i> How could this be?</i> <i> Top-down realization?</i> <i>But give reductionism a chance.</i> <i> Reductionism is how
the world works.</i> <i> All, in principle,
can be explained by physics,</i> <i> although all, in practice,
cannot be.</i> <i> If fundamental physics
would be forever not capable</i> <i> of explaining biology or
psychology or anything else,</i> <i>if that reduction could not ever
be made, then one must conclude</i> <i> that there are mechanisms
by which the microworld evolves</i> <i> which cannot be accounted
for in terms of physics.</i> <i> Is this a contradiction?</i> <i> Yes, if reality is confined
to the physical,</i> <i> but there is no contradiction</i> <i> if one dares venture beyond
the known physical world.</i> <i>Although I have to be a skeptic,</i> <i> discerning Strong Emergence
brings us closer to truth.</i> ANNOUNCER:<i>
For complete interviews</i> <i> and further information,
please visit closertotruth.com.</i> [♪♪♪]
