Good evening.
My name is Joaquin Ruiz.
I'm dean of the
College of Science.
And I welcome you all to today's
lecture from our series, Next.
Today, we have the
pleasure of having
with us one of the premier
philosophers from the world,
actually, and from
this country for sure,
Dr. Dennett, who will be telling
us a little bit about how
we have changed our views
about things since Darwin.
This lecture series, this is
the fourth lecture series now
that the College of
Science has produced.
And as I was telling somebody
as I was walking down the aisle,
this is quite a
symbiotic kind of thing.
And we will be happy to
continue these lecture series
as long as you keep showing up.
And in fact, I'm incredibly
proud to be in a community that
brings as many people as
we do in our community
to listen to science.
These lectures are expensive.
And there are many people
that support the lecture.
Cox Communication, Bob
Davis, the Galileo circle,
who are members of
our community that
support the College of Science,
[INAUDIBLE] Design, Tom
and Candy Grogan, Jeff and
[? Shelley ?] Owen, Raytheon,
Research Corporation,
and UniSource Energy.
Today, I am thrilled, in fact,
that the individual that's
going to be
introducing our speaker
is Dr. Taylor, who is
the president of Research
Corporation in town.
So it ends up being that
this high tech energy has
a humanist running it.
And he will be introducing
our speaker tonight.
Taylor Lawrence, where are you?
Thanks, Dean Ruiz.
I'm actually
president of Raytheon.
A little bit bigger,
but you know.
But it's a pleasure to be here.
I moved from our corporate
headquarters in Massachusetts
back in June to take over for
Louise Francis Francesconi who
retired on July 1.
I must say I'm not missing
the winter weather back
in Massachusetts.
But I also have to say that
on a night like tonight when
it's below 60, people think it's
very wicked weather here too.
So I appreciate all
of you coming out
on such a horrid night
here in Arizona to attend.
Well Raytheon is
very proud to be
a part of this lecture series.
We're in our fourth year
of providing support
to make this free to the public.
And one of our
struggles at Raytheon,
and I recently spoke
to the Board of Regents
here at U of A,
is promoting math,
and science, and engineering,
and technology education
to our young people, and getting
them excited about careers
in STEM types of fields.
And I'm very, very
disturbed by some
of the things that are
going on in our community
today, especially
with the economy
and with some of the
actions of our legislature.
And strongly support
strong funding
for the University of Arizona.
And I hope we can turn
a corner and come back.
Because we need
a steady pipeline
of talent in this state.
We need it to preserve
the high technology
jobs that we have in the state.
And I feel very privileged that
we have such a fine university
and a distinguished
college of science
right here-- right
here in Tucson.
And one of the things
I've learned about
is U of A's Ecology and
Evolutionary Biology
Department.
I didn't realize
that in 1975, it
was the first of its
kind in the world.
And now most of the
top universities
have EEB departments.
But ours is ranked in the
top 10% of all such programs.
And just as impressive, the
physical sciences at the U of A
were recently ranked number
one by the National Science
Foundation among
all universities
within the United States.
And tonight, in celebration
of Darwin's 200th birthday,
I'm honored to introduce
Dr. Daniel C. Dennett.
Dr. Dennett is university
professor, an Austin B.
Fletcher professor
of philosophy,
and co-director at the Center
for Cognitive Studies at Tufts
University.
He received his BA in
philosophy from Harvard in 1963,
the year I was born.
So I'm kind of a young guy.
He then went to Oxford to work
with Gilbert Ryle, under whose
supervision he completed the
DPhil in philosophy in 1965.
He taught at UC-Irvine
from 1965 to 1971
when he moved to Tufts, where
he has taught ever since, aside
from periods visiting at
Harvard, Pittsburgh, Oxford,
and the [INAUDIBLE] in Paris.
He's the author of a book
that's a favorite of mine.
In fact, I pulled
it out of my library
and brought it along--
Darwin's Dangerous Idea.
I bought this back in 1995.
It's been in my
library ever since.
His most recent book,
Breaking the Spell:
Religion is a Natural
Phenomenon was published in 2006
by Viking Press.
He has received two Guggenheim
fellowships, a Fulbright
fellowship, and a
fellowship at the Center
for Advanced Studies
and Behavioral Science,
and many, many other awards.
Ladies and gentlemen,
please join me
in welcoming Dr. Daniel Dennett.
Thank you very much.
I am honored to be here
and to see so many of you
in this audience.
This is a special
occasion indeed.
But let's get started.
As a philosopher, I
have to face the fact--
and all philosophers
do, I think--
that some of the
greatest thinkers
that we philosophers have to
consider were not philosophers.
Here's five of the
most important.
I haven't labeled them so
you can see who they are.
All right.
Call out the names.
Starting from left
to right it is?
Newton
Newton.
Next.
Einstein.
Yes.
Next.
[INAUDIBLE]
Yes.
Who's the next one?
Godel.
Godel.
Yeah, that's right.
That's Kurt Godel.
And finally there's?
Turing.s
Turing.
OK.
Indeed, you're right.
So these are all philosophers
who weren't philosophers--
very important thinkers
who are important
to philosophical thought.
But the number one
philosopher, in my opinion,
who wasn't a philosopher has got
to be this one, Charles Darwin.
Now when I show this
picture sometimes
I get a sort of laugh.
I don't know what this is about.
I don't know why.
I don't, myself, see any
reason for that laugh.
But we can get it
behind us, and then we
can get on to other things.
So why was Darwin's
idea so great?
I think the answer is really
quite straightforward.
Darwin's idea of evolution
by natural selection united
the two most disparate
parts of our universe--
the world of purposeless
causation on the one hand--
the world of physics
and chemistry--
with a world of meaning-- the
world of ethics and poetry.
So we go all the way from
physics to ethics and poetry,
and even beyond
that to morality,
all in one unified perspective.
No other scientific idea
or philosophical idea
so grandly unifies
everything that exists
under a single perspective.
It's not as if there wasn't
an earlier perspective that
had the same aspiration.
The pre-Darwinian
world view is made
famous-- among other
places-- in the ceiling
of the Sistine
Chapel, Michelangelo's
famous paintings.
And in the center, we
see God, the Creator,
putting the finishing
touches on Adam.
I want to call this
the trickle-down theory
of creation.
Adam is pretty wonderful, but
he is the creation of something
more wonderful still.
Adam is pretty smart, but
his creator is even smarter,
even more intelligent.
And I think that this idea
may have even been obvious.
Even to our ancestors,
this may be an idea
that's older than our species.
Homo habilis was a hominid
that made very simple tools--
chipped stone flakes mainly.
And I think that maybe Homo
habilis had some dim sense
that it always takes a
big, fancy, smart thing
to make a lesser thing.
You never see a pot
making a potter.
You never come across a
horseshoe making a blacksmith.
It's always big, smart, fancy
things making lesser things
of one sort or another.
That's the trickle-down
theory of creation.
And it seems, indeed,
quite obvious.
Along comes Darwin with what we
may call the bubble-up theory
of creation.
And here, I though,
Darwin's birthday,
we really should have a little
quotation from Darwin himself.
And what I've chosen is
simply a great long sentence
at the end of chapter
four of Origin of Species,
which captures all on one page
the main points of the theory.
It has often been said
one long argument.
I'm going to bring out the
argument by highlighting it.
"If, during the
long course of ages
and under varying
conditions of life,
organic beings vary at
all in the several parts
of their organization.
And I think this
cannot be disputed."
He puts in a little empirical.
He says, that's a premise
that everybody should accept.
"If there be owing to the high
geometric powers of increase
of each species that some
age, season, or year,
a severe struggle for life, this
certainly cannot be disputed.
Then considering the
infinite complexity
of the relations of all
organic beings to each other
and to their conditions
of existence causing
an infinite diversity and
structure of constitution
in the habits to be
advantageous to them,
I think it would be a
most extraordinary fact
if no variation ever had
occurred useful to each beings
own welfare in the same way
that so many variations have
occurred useful to man."
Now the punchline.
"But if variations useful to
any organic being do occur,
assuredly individuals
thus characterized
will have the best
chance of being preserved
in the struggle for life.
And from the strong
principle of inheritance,
they will tend to
produce offspring
similarly characterized.
This principle of
preservation I have
called, for the sake of
brevity, natural selection."
That's it.
That is a beautiful, succinct
summary of Darwin's great idea.
On the face of it, it
may not seem so shocking.
But to many people, it seemed to
be a deeply subversive and even
outrageous idea.
A critic named MacKenzie
summed it up-- not right away,
but in 1868 in a piece published
in the Athenaeum, which
was sort of the London
Review of Books of its day.
And here is MacKenzie's
observation about this theory.
"In theory with which
we have to deal,
absolute ignorance
is the artificer so
that we may enunciate as
the fundamental principle
of the whole system
that in order
to make a perfect,
a beautiful, machine
it is not requisite to
know how to make it."
The capital letters
are in the original.
This is a man in high dudgeon.
"This proposition will be
found, on careful examination,
to express in condensed
form the essential purport
of the theory, and to
express in a few words
all Mr. Darwin's meaning--
who, by a strange inversion
of reasoning, seems to think
absolute ignorance fully
qualified to take the
place of absolute wisdom
in all the achievements
of creative skill."
Exactly.
That's it.
He's got it.
That's just exactly the
purport of Mr. Darwin's theory.
It is a strange
inversion of reasoning.
It flies in the face of
common sense principles
that go back to Homo
habilis perhaps.
So obvious does it seem to so
many people that this cannot be
right that a creationist
pamphlet that was sent to me
by a student sort of mocks it.
Test two.
Do you know of any building
that didn't have a builder?
Do you know of any painting
that didn't have a painter?
Do you know of any car
that didn't have a maker?
If you answered yes for any
of the above, give details.
Ah ha.
This challenge thrown in
the face of Darwinians
perfectly expresses the sense
of just utter incredulity
with which many people
greet Darwin's great idea.
And yet Darwin says,
no I can't show
you a building, or a
painting, or a car.
But everything in the biosphere
has exactly this property
that you find so
impossible to accept.
I mentioned Alan Turing
a few minutes ago
as another great thinker.
And I want to point out a deep
commonality between this Brit
and that other Brit,
Charles Darwin.
I want to talk about Turing's
strange inversion of reasoning
so that you can compare the two.
Before Turing, there
were computers.
Mostly they had
degrees in mathematics.
Some of them, as you
can see, wore dresses.
They were people.
That was their job.
They were called computers.
They worked in offices,
and they did computation.
In the old days, computers
had to understand arithmetic,
had to appreciate the reasons
for what they were doing.
Turing recognized that
this was not a necessity.
In his 1936 paper on
computable numbers,
he puts it this way-- "the
behavior of the computer
at any moment is determined
by the symbols which
he is observing and his
state of mind at the moment,"
putting "state of mind"
in quotation marks
to suggest that this was
an illimitable feature.
So now let's compare
Darwin and Turing.
Here's Darwin strange idea, his
strange inversion of reasoning.
And I've used MacKenzie's
words in their caps.
And here's Turing's.
"In order to be a perfect and
beautiful computing machine,
it is not requisite to
know what arithmetic is."
Now this strikes many people
as just about as preposterous
as Darwin's inversion.
Although we do know,
thanks to the last 75
years of computer development,
that, indeed, it is true.
Indeed, Turing's strange
inversion is widely-accepted.
Put the two together.
"In order to make a perfect
and beautiful machine,
it's not requisite to
know how to make it.
In order to be perfect and
beautiful computing machine,
it is not requisite to
know what arithmetic is."
In fact, they're
almost the same point
applied in different domains.
Now many people just can't abide
Darwin's strange inversion.
We call them creationists.
Oh, what happened?
I left out something.
There.
There are other
people who are not
creationists who
also can't abide
Darwin's strange inversion.
There are many people
who can't abide
Turing's strange inversion.
I propose that we might
call them mind creationists.
And there are even a few
people who seem to be both.
In fact, a few very
eminent people.
Simon Conway Morris,
the paleontologist.
Jerry Fodor, Thomas Nagel-- two
very well-known philosophers.
Thomas Nagel in a recent
piece in Philosophy and Public
Affairs.
John Searle, who has argued
that what he calls original
intentionality cannot be
achieved by, shall we call it,
Turing's strange inversion.
Searle treats the mind as
what we might call a skyhook.
So let me explain
my terminology.
What is a skyhook?
In Darwin's dangerous
idea, I draw a distinction
between skyhooks and cranes.
The way to understand this is
to recognize the work of design
can be considered to be
lifting in design space.
Imagine the space of all
possible designs of every sort,
artificial and natural.
And think of the work of R&D,
research and development,
as lifting.
It takes energy.
It takes time in design space.
Now intelligent design, or
the work of intelligence,
can be considered then
lifting in design space.
Then skyhooks are
miraculous top-down lifters.
They are things that just float
high in that space somehow
without being the products
of a laborious process
of non-miraculous R&D. Cranes,
in contrast, do good lifting.
But they've been put in position
by non-miraculous bubble-up
processes.
So now we have this
metaphor for understanding
the relationship between
Darwin's idea and his critics.
Darwin's bubble-up theory
says, over billions of years,
non-miraculous,
non-intelligent forces
have gradually created
more and more design.
And among those
designs are cranes
which speed up the lifting,
make the lifting more efficient.
And by these processes
cascaded together,
we can get anywhere in design
space where anything exists.
How do you rebut that?
You look for something
that couldn't
be arrived at by that bubble-up
process-- something that
had to come into existence just
hanging there in design space
thanks to some special act
of intelligent creation.
It can seem that some design is
too wonderful to have evolved.
It's irreducibly complex,
requiring a top-down helping
hand.
So what critics and
skeptics of evolution
have been looking for
150 years are skyhooks.
They want to have examples
of living things, phenomena
in the biosphere, that are so
marvelous, so supercalifragili
sticexpialidocious,
that there's just
no path from the Darwinians'
starting point up to them.
They are irreducibly complex.
Over the years,
hunting for skyhooks
has actually led to
some very good science,
because people have
looked for skyhooks
and they've discovered cranes.
They think it's impossible that
the following thing could ever
evolve.
They set out to prove
that it's impossible.
And they end up discovering
some new lifting device that
makes it possible after all.
I'm going to discuss a
few in a few minutes.
Now of course, when I
talk about skyhooks,
this is not what I have in mind.
Somebody sent me this
photograph recently.
Apparently there's
a lighter than air
company somewhere-- I
think in Europe-- that
makes what they call skyhooks.
These are really cranes,
because they're non-miraculous.
This is a skyhook.
This wonderful, satiric drawing
appeared in the Atlantic
Monthly a few years ago.
And it's particularly
appropriate,
because those of you
who are into art history
will recognize that
this is Brunelleschi's
dome in Florence.
And at the time it was built,
it was an engineering marvel.
It was considered one of the
great, almost nearly miraculous
structures in the world.
And placing that
lantern on the top
was the crowning achievement.
This is not, of course, how
Brunelleschi achieved that.
In fact, how he achieved
it was by inventing
a whole new series
of cranes that
had never been seen before.
And those cranes--
they're like these.
These are not actually
Brunelleschi's drawings.
These cranes made
possible the exploration
of parts of architectural
design space that, heretofore,
had not been accessible.
That's how cranes operate.
Well now many people, when
they think about evolution,
they accept that evolution can
explain some things and not
others.
For instance, they're inclined
to say, yeah, yeah, yeah.
I think evolution can
explain say, a nightingale,
but not an ode to a nightingale.
Really?
You think an ode
to a nightingale
is that much more wonderful
than a nightingale?
Think of the intricacy, the
wonderfulness of a nightingale.
If that can be
produced by ultimately
mechanical,
non-miraculous processes,
you don't think a
poem could be produced
by somewhat different but
also non-miraculous processes?
This is a good example
of the resistance
that is felt in many quarters
to the Darwinian perspective.
People say, well yes.
I see how the bubble-up
theory of creation
can explain a lot of
things-- birds, beaver dams--
but not poems and
not the Hoover Dam.
I think this is
very short-sighted.
Now I want to sketch
the bubble-up path.
It'll have to be a
sketch, because there
isn't that much time.
Because along the way, I
think we get some insights.
What we see here is a
cover of Science Magazine
a few years ago.
And what it shows is a
motor protein trudging along
inside a cell.
Now I've used this
diagram for some time.
And just recently, I
discovered a superb animation
of a motor protein--
much more realistic
than this, which I
want to share with you.
We're made of trillions
of these little fellas.
Really, we are.
You have trillions of
these in your body.
Not millions or billions.
Trillions of them.
You couldn't live without them.
And they are not even alive.
They're proteins.
They are motor proteins.
So we're made of trillions
of mindless little robots.
Not a one of them knows
who we are or cares.
In fact, not a one of
them knows a darn thing.
They are, as MacKenzie would
say, absolutely ignorant.
But stop.
We know.
We care.
How can this be?
How come?
How can things that care,
and understand, and know
be constructed out of mindless
little robots by the trillions?
That's the task for the
Darwinian bubble-up path
to explain.
Along the way, there were
some very important cranes.
And the one I want
to concentrate on
is eukaryotic revolution,
which takes us back roughly two
and a half billion years.
Life began on this planet
about a billion years
earlier than that.
So for a billion years, all
there were on this planet
were simple cells-- so-called
prokaryotes like bacteria.
And then one day, a
wonderful thing happened.
Prokaryote A, prokaryote
B bumped into each other.
And instead of B eating A or
A eating B from the inside,
B left A intact.
And A and B joined forces to
become a single thing-- an AB.
And in this refraining
from eating, you might say,
well it's a good meal.
But instead of
having a good meal,
picked up a billion years of
independent R&D incorporated
into the structure
of that thing,
giving it an instant
multiplication of competence.
It joined forces
with the cell, taking
advantage of all that design.
Lynn Margulis is the scientist
at UMass who is responsible,
I think, for weathering lots
of storms and getting people
to take this idea
seriously when they didn't.
It is now textbook fare.
And many, many
demonstrations and proofs
of this, the symbiotic origins
of the eukaryotic cells.
And the eukaryotic cells
are bigger and more complex.
They have more moving parts.
On the left, you see a sort of
simple sketch of a prokaryote.
On the right, a eukaryote.
And you see the
little yellow ovals.
Those are mitochondria.
They have their own DNA, just
the way the prokaryote does.
In fact, you have
your mitochondrial DNA
and you have your nuclear
DNA in the nucleus.
So there are sort of
two genomes right there.
And every cell in your body,
every human cell in your body,
is a eukaryotic cell.
And it has its nuclear
DNA, that's your genome.
And it has its
mitochondrial DNA.
And that DNA is descended from
that original endosymbiotic
revolution.
Eukaryotes are more complex.
They're more talented.
They're more versatile.
This versatility permitted
a division of labor.
And that permitted
multi-cellular life,
because you could have bone
cells, and blood cells,
and liver cells,
and brain cells,
and all the other kinds of
cells-- all eukaryotic cells.
By being versatile
and by specializing,
they could create this
division of labor,
which makes multi-cellular
life like you and me,
and like every plant and every
animal on land or in sea,
they're all eukaryotes.
Here's one.
Not a very fancy one.
It's a caddis fly larva.
Here's something that it builds.
It's a food sieve.
It lives in the water.
It builds this amazing
structure in the flowing water.
The water flows in, as
you can see in the funnel.
The food gets
trapped on the sieve.
The water escapes.
And then the larva can
just scrape up the food
off the sieve.
This is quite an
ingenious artifact,
I think, you'd have to believe.
And it's made by such a simple
organism, a caddis larva.
It bears a certain striking
resemblance to this food sieve.
Some similar features,
some similar purposes.
What's the difference
between them?
The difference between them is
that although there are reasons
for the arrangement of the
parts in the caddis larva's food
sieve, and there are
also in the lobster trap,
they're not
represented anywhere.
They're not represented in the
caddis larva's nervous system.
They're not represented
in natural selection.
They're not represented at all.
Whereas in the case
of the lobster trap,
the reasons for the
parts are represented
in the minds of the people
that make lobster traps,
or the people who
order lobster traps,
or the people who
design lobster traps.
These reasons that we see in
the case of the caddis larva
are what I call free-floating
rationales of evolution.
They are the reasons why
structures in the biosphere
have the shapes and
parts that they do.
But they're not reasons that
were represented anywhere
until some clever
biologist figured them
out and represented them.
But that had nothing to do with
their coming into existence.
One of my favorite examples
is the cuckoo chick.
Now cuckoos are brood parasites.
Cuckoos do not make
their own nests.
The cuckoo mother, when
she's ready to lay her egg,
finds the nest of another
species that's just been built.
The eggs have been laid.
And she waits in hiding,
watching until the parents that
have built that nest and laid
those eggs fly away to feed.
Then she swoops down,
lays her egg in the nest,
rolls one of the host eggs out.
That's just in case
the host can count.
That's the reason.
And goes away, flies
away, never to return.
The hosts come back.
Things look all right.
They incubate the eggs.
And the cuckoo egg incubates
faster than the others.
So the cuckoo chick
is the first one out.
And the first thing it
does is to try to roll
the other eggs out of the nest.
This is an artist's sketch.
But I want to show you
a little film clip.
The cuckoo's egg looks
like the warbler's.
And the number of
eggs hasn't changed.
Everything appears normal, but
appearances can be deceiving.
Something is not quite right.
One chick has hatched
way before the others.
And it is ejecting
the remaining eggs.
I think you have to
agree there's plenty
of sign of purpose there.
The reason for this
behavior is all too clear.
But relax.
The cuckoo chick doesn't
understand the reason.
It doesn't have to
understand the reason.
It knows not what it does.
Natural selection
tracks that reason.
And it creates things that have
purposes such as that purpose.
But organisms themselves don't
need to know their purposes.
The need to know principle
reigns in the biosphere
just as it does at the CIA.
But it has a different.
Rationale in the
CIA, the reason why
the need to know principle
is invoked-- only
give your agents the information
they absolutely need to know--
is because then if they're
captured, and tortured,
and spill the beans, they
don't have many beans to spill.
That's one reason for the
need to know principle.
Evolution's reason is
rather simpler-- thrift.
If an organism doesn't need to
know the reason why it's doing
something, don't provide it.
The organism will do just fine.
It will be the beneficiary
of that purpose
without comprehending it at all.
Now there's a common error when
people study-- and not just
lay people, even scientists--
when they study animals
that exhibit such purposes.
What happens is we attribute
more understanding to the agent
than need be.
And the reason for
this, I submit,
is because we lack
a familiar concept
of what we might
call semi-understood
quasi-representations.
There's no term for that.
Or hemi-semi-demi-understood
pseudo-representations.
There's just no everyday
words for these things.
This is where Turing comes in.
It is Turing's
strange inversion that
gives us the vocabulary
and the concepts
to think about such strange and
unnatural states of affairs.
Computer programs that
don't really understand,
but they sort of understand.
And those aren't
really representations.
They're only sort
of representations.
But they get the job done.
Now sometimes
birds can do things
that are much more
dramatic and interesting.
And I'm going to
show you an example.
So this is a New
Caledonian crow.
No sound on this.
It's been given just
a piece of wire.
And it's trying to get some
food out of this beaker.
No success.
Here's the tree of life.
It doesn't look much
like a tree of life,
because we're looking at
it from the bird's eye view
actually-- from on top.
And the root, you
can see at the center
there where that Y is, that's
the last universal common
ancestor of everything
alive on the planet today.
And you see the
bacteria on the left
and the archaea up
on the upper right.
And down on the bottom
here, we see the eukarya,
the eukaryotic cells.
And it's been drawn
so that out at the end
of the eukaryotic
branch, there's
three closely-related
genera-- [INAUDIBLE],
homo, and [INAUDIBLE].
Homo, of course, is us.
The other two are close
relatives, relatively speaking,
of us.
That's mushrooms, us, and corn.
Yes.
You are closely related to corn.
You are closely
related to mushrooms.
You have more genes in
common with each of them
than you do with the other
branches on the tree of life.
All of that tree of
life-- oh, here's
another, better, more recent
picture of the eukaryotes.
I won't bother explaining that.
Time is short.
All of that has to happen about
three and a half billion years.
We split off from our common
ancestor with the chimpanzee
roughly six million years ago.
And it is just as
wrong to say that we
evolved from chimpanzees as to
say that chimpanzees evolved
from us.
We both evolved from
a common ancestor.
Chimpanzees have been evolving
away from that common ancestor
just as long as we have.
But probably that ancestor was
a lot more, in most regards,
like a chimpanzee
than it is like us.
But in any case, the
differences between us
and the chimpanzee
all have to have
been accumulated
by R&D that occurs
in the last six million years.
But now I want to
leap ahead, ignoring
all the interesting complexities
about hominid evolution,
and go to the
recent, recent past
when Homo sapiens,
when our species,
was already well-established
around the time
of the dawn of agriculture.
Paul MacCready the
visionary engineer,
the creator of the
Gossamer Albatross,
calculated a few years
ago that at that time--
shortly after the dawn of
agriculture-- human beings
plus all their livestock
and all their pets
was just a fraction of 1% of the
terrestrial vertebrate biomass.
That is to say that
doesn't include
the insects or the worms.
It doesn't include
the fish in the sea.
This is the terrestrial
vertebrate biomass,
roughly what everyday
folks call animals.
So us plus all our
animals was less
than a fraction of 1%
just 10,000 years ago.
What do you suppose it is today?
Quite a bit more.
What do you think, 20%?
30%?
50%?
How could it be 50%?
MacCready calculates
that it's 98%.
Now most of that's cattle.
We plus our domesticated
animals have swamped
the world in just 10,000 years.
Here's what MacCready
has to say about it.
"Over billions of years
on a unique sphere,
chance has painted a
thin covering of life--
complex, improbable,
wonderful, and fragile.
Suddenly, we humans--"
forget the parentheses.
It's false.
"--have grown in
population, technology,
and intelligence to a
position of terrible power.
We now wield the paintbrush."
All of this in 10,000 years.
As he says, it's the
technology and intelligence
that permit us to do this.
Compare the Cambrian
Explosion, which
was another great event
in the history of life.
It occurred over
millions of years
and it occurred about
530 million years ago.
That's when so many new
body plans evolved over
a relatively very
short period of time,
and created so much of the
diversity of life forms.
This has been famous
by Steve Gould
in his book, Wonderful Life.
And that was, indeed, one of
the great explosive creative
periods in evolution.
But compare that with the
MacCready explosion, which
occurred over 10,000 years.
That's only about 500
human generations.
It's a remarkably
swift biological change
to the planet.
And we're right at
the center of it.
It's not just genes.
There's a second
information highway
from parents to offspring
that we, and really we alone,
have optimized.
Richardson and Boyd, in
their wonderful book,
Not by Genes Alone,
examine the conditions
under which this could happen.
And they point out that culture
is transmitted more generally
than genes.
You get your genes
from your parents.
That is vertical transmission.
But once this second highway
from parents to offspring
is established, you
can then get what
they call oblique
transmission, or even
horizontal
transmission, where you
get a lot of this information
not from your parents
but from your peers, from other
people, people not related
to you at all.
Once this information highway
is established between parent
and offspring, it can be
co-opted and exploited
by all of these other
elements, which they
call rogue cultural variants.
To get the idea, you might want
to think about the internet
and spam.
The internet wasn't created
to make spam possible.
It wasn't created to make
pornography possible.
But once it exists
and is in good shape,
all kinds of rogue
cultural variants
begin to take advantage
of it, as we all know.
Those rogue cultural variants
are what Richard Dawkins
calls memes--
cultural items that
replicate and spread
through human populations
thanks to their culture.
Memes, says Dawkins,
are analogous to genes.
They're information structures.
They bear information.
He also points out that
they're analogous to viruses.
And what is a virus, actually?
It is really a
sort of naked gene.
It's just sort of
all gene and no body.
Or as I like to say,
a virus is a string
of nucleic acid with attitude.
It doesn't have a mind.
It is absolutely ignorant.
But it does have the amazing
competence, the competence
of being able to insert
itself because of its shape
into a cell that does
have copy machinery there.
And to commandeer
that copy machinery
and get it to make
copies of itself, rather
than of the cell's own DNA.
That's how viruses replicate.
And of course, natural
selection operates over them
very effectively.
To take a well-known
example, HIV, a virus,
a non-living replicator,
has evolved more just
in terms of codon change
since it was first
sequenced not so many years
ago than we have evolved
from our common ancestor
with the chimpanzee
six million years ago.
It's very fast.
A meme is a data structure made
of information with attitude.
It's the same sort
of thing as a virus.
But it doesn't insert itself
into an individual cell
and get the cell's Cells
copy machinery to work.
It inserts itself into an
individual head, into a brain,
and gets the brain
to make the copies.
And then to spit them
out, to transmit them,
to broadcast them, the
way I'm doing right now.
I am spraying you with
memes, some of which
are no doubt going to enter not
only your ears, but your minds.
And there they will
proliferate and replicate.
And then you'll spread
them to somebody else.
And it will be viral.
You get the idea.
Let's put in a little
skeptical interlude.
What evidence is there
that memes even exist Well
if you believe that
words exist, then you
believe that memes
exist, because words are
memes that can be pronounced.
There are other
memes that can't be.
But words-- how many of
you believe in words?
All right, they're memes
that can be pronounced.
If you doubt the
existence of words,
then you can doubt the
existence of memes.
In other words, we're
apes with infected brains.
Or you might say
we are euprimates,
like those eukaryotic cells.
Our brains are invaded by
virtual machines designed
by natural selection.
And these virtual
machines give us
powers, which give
us the versatility
to take organization up a level.
Remember that original
endosymbiotic origin
of eukaryotes?
Where B got a billion years of
R&D for free by just joining
forces, by just taking that
other prokaryote in and not
eating it, not taking
it apart, because that
would have lost all
the information--
or most of the information.
Similarly, when you take in
memes, you don't eat them.
You don't take them apart.
You leave their
structure intact,
because that's the product
of many years of design.
None of you had to invent
the wheel, or long division,
or statistics, or finding
averages, or reading maps.
All of these wonderful
tools are culture-born.
And you just help
yourself to them,
and you pack them
into your head.
Our power depends
on the culture that
permits us to divide labor and
share expertise so that we can
create organizations like
universities, like churches,
like armies, like clubs,
like institutions,
which depend on a
division of labor
and depend on our complexity.
From this perspective,
we're able to see
that among the fruits
on the tree of life
are both spiderwebs and
power grids, both beaver
dams and the Hoover Dam, both
the bird's nest and the ode
to a nightingale.
These are all artifacts
made by organisms.
And in the case of
the human organisms,
these are artifacts
that are made
possible by the
establishment in those brains
of evolved virtual
machines-- memes-- that
give them their powers.
So now I want to approach
the delicate transition
from bottom-up Darwinian R&D to
top-down creative genius R&D,
because after all, we do have
this clear image that sometimes
people are really geniuses.
And they're really creative.
They are intelligent designers.
Well as Bo Dahlbom once said,
"You can't do much carpentry
with your bare hands, and
you can't do much thinking
with your bare brain."
If you're going to do some
really creative thinking,
you need lots of thinking tools.
Fortunately, there's a
lot of them lying around.
Those are those memes that
I was telling you about.
And so you take them in,
and you make them your own,
and you learn to use them.
And that equips your mind with
all sorts of prosthetic devices
that you can then
use to create things.
So what I'm suggesting is
that words are sort of tools.
They're not always elements
in grammatical constructions.
For instance,
passwords and labels
are individual words
that have very nice uses
quite independently of any
grammar, of any syntax.
Interestingly enough,
both passwords and labels
are echoes of designs
that evolution
has found much earlier in
the animal world, as well.
We've sort of
rediscovered tricks
that evolution
discovered long ago.
My dear friend and sometimes
co-author, Doug Hofstadter,
in his 2006 book, I
am a Strange Loop,
gives us a list, a toolkit.
And it includes a wonderful
list of tools in his kit.
And they're in your kit too.
Here they are.
Wild goose chases, tackiness,
dirty tricks, sour grapes,
elbow grease, feet of clay,
loose cannons, crackpots,
lip service, slam
dunks, feedback.
Each of these is
a thinking tool.
If you've got it, if
it's part of your kit,
you can think more effectively,
more efficiently, more swiftly.
You can categorize things.
You can find similarities.
You can reason about
similarities better
with these tools than
you could otherwise.
These are tools that are
made of not steel, and wood,
and so forth.
They're made of technique.
They're made of information.
They're recipes for action.
And some of them
are obviously that,
like long division
is a nice tool.
Statistics is a nice tool.
They're rather like
Java applets if you're
into thinking about
these in computer terms.
They're informational
structures that
enhance the powers
of the Turing machine
that you have between your ears.
What are Java applets made of?
They're made of information.
Well they're made of bits.
But they have no material
basis other than that.
And much is the same of words.
What's long division made of?
It's an algorithm.
It's made of just information.
It's a recipe for
doing something.
What's cost benefit
analysis made of?
These are excellent tools that
are not made of any material.
They're made of information.
They are, as we say,
virtual machines.
And this is the technology
that has remade the brain,
and basically that
makes the human minds.
Now who designs all these
treasures that we share?
Well there are heroes of design
that can be assigned authorship
for some of those treasures.
People like Pythagoras,
and Plato, and Descartes,
and Newton, and Shakespeare,
and Austen, and Curie,
and many others.
But in general, no.
Most of the treasures that you
have stored up in your head
have no authors at all.
Nobody designed language.
Nobody designed tonal music.
But then what are you?
What am I?
Who uses these tools?
Is there a Cartesian
ego in there that
equips itself with the tools?
No.
That is not what is in there.
What is in there
is just an alliance
of hemi-semi-demi-understood
quasi-representations.
Just a whole bunch
of memes in there,
forming a superstructure, which
then has the interesting role
of being a virtual machine
made of smaller, simpler
virtual machines.
And it guards the
entrance and evaluates yet
other virtual machines.
This still looks
ominous to most people.
But I want to try to take away
the bad aroma of this idea
by pointing to
something that Darwin
did in the Origin of Species.
He began that book by looking
at methodical selection.
That is, where plant and
animal breeders set out
with foresight,
and deliberately,
and with intention,
with consciousness
to try to improve the
breed, to make a faster race
horse, a smarter dog, a more
beautiful pigeon, and so forth.
And then he pointed
out that that works.
But also so does what he
calls unconscious selection.
This is where people,
without intending a thing,
without meaning a thing,
without knowing what they're
doing inadvertently,
their actions
tend to bias the survival
of their domesticated plants
and animals.
And this leads to
accumulated change
in those domesticated species.
This is still going on today.
And then he uses that as a
segue into natural selection.
So we start with an
attempted intelligent design.
And then we get design which
isn't really intelligent.
It's just unconscious.
And then we get
natural selection
where there's no
mind involved at all,
just the vicissitudes of nature.
Now more recently, of course,
we've added one at the top.
We've added genetic
engineering, which
is like methodical selection,
only more efficient,
in that we don't wait for nature
to generate the genomes that we
then put to the test.
Now we can do the
same thing with memes.
Working backwards, let's
start at the bottom,
working in the other direction
from the previous slide.
First we have what we might
call the natural selection
of synanthropic memes.
Synanthropic memes are the rats,
and bedbugs, and squirrels,
and pigeons of the meme world.
They're not domesticated.
We don't own them.
We don't love them.
They're well-designed
by natural selection
to live in our company and to
exploit us in various ways.
But pretty soon, we get
unconscious selection
where we have, for
instance, tunes
that replicate and only
the most memorable,
the most unforgettable,
the most lilting tunes
survive and make copies.
And the rest go extinct.
And you get what
the Germans call
earworms, those terrible
tunes that you can't get out
of your head.
You don't like it.
You don't want to own it.
You're just stuck with it.
And now you're going to pass
it to your neighbor, who's
going to hate you for it.
But there are memes that
we love, that we honor,
that we respect.
And we go way out of
our way to make sure
that they replicate in our
children, in our friends,
in our young.
And like other
domesticated species--
like laying hens for instance,
which would probably go extinct
if they were left on
their own in nature,
because their capacity to
reproduce and to incubate
their eggs has been pretty
well bred out of them.
So people have to work hard
to get hens to reproduce.
And similarly, I'll give
you an example-- calculus.
Or maybe here at UA, people find
this just the most wonderful,
infectious idea.
You just can't get
it out of your head.
So catchy, calculus.
So infectious.
Just can't get those
derivatives out of my head.
I doubt it.
No these memes have to be very
deliberately and laboriously
replicated generation
after generation.
And then, of course, we have
memetic engineering, which
is what people in advertising
do, and spin doctors,
and other people who try
to do intelligent design
of cultural items
that will then fly,
that will become
viral, that will
pass from person to person.
What this all permits us
to do is a certain sort
of bootstrapping.
It's worked in the past
and it'll work again.
I'm going to give you one
example of bootstrapping,
which should stand for
thousands actually.
How do you draw a straight line?
Think about it.
It's easy.
Get a piece of paper, and a
pencil, and a straight edge.
And put the straight
edge down on the paper.
You draw the line.
That's how you do it.
It's easy.
Use a straight edge.
Where'd you get
the straight edge?
Oh, you got the straight
edge from a straight edge
manufacturer.
How do you make
the straight edge?
Well you see, he had
this straight edge.
And he put a piece
of metal down.
And where did he get
his straight edge?
Well from a super straight edge
manufacturer, and so forth.
But that's not an
infinite regress.
It's a finite regress.
And it turns out to be a
fairly interesting one.
This is from a 1970 book.
And it shows a circa 1960
high quality straight edge,
about as good as you
could make at that time.
The history of the
evolution of straight edges
is really quite an
interesting phenomenon.
They got better and better.
And one of the key elements
in their getting better
is that they began to
use their other memes
to represent the
goal of making better
and better straight edges.
Here is a wonderful
diagram from that book.
That wiggly line
that you see there
is a representation
of a straight edge,
as good a straight edge as
they could make in 1960.
It's a gauge block.
And it shows the
imperfections in that surface
magnified a million fold.
Once you've got the capacity
to represent your reasons
for making things, unlike
the caddis fly larva,
once you can
represent the reasons
and then represent the falling
short of the perfections
that you can define, you're
on an accelerated path
to competence.
The ideal of a perfectly
straight line--
or as Plato might say,
the form of the straight--
was arrived at by approximation,
both of the artifacts
and of the idea itself.
The form of the good
has a similar history.
And for that matter,
the form of the true.
What makes us human
then is not so much
our genetic children
as our brain children.
We alone represent our reasons.
We can think about our
values, our reasons.
And that is the source
of our creativity.
We, the reason representers,
now can look back
and discover the
reasons everywhere
in the tree of life, the
unrepresented reasons for all
of the parts in the tree of
life before here, before us.
It took Darwin to discover
that a mindless process created
all those reasons.
We intelligent
designers then are
among the effects, the
very recent effects--
not the cause-- of
all those purposes.
Some of you may notice I have a
little Darwin fish, an evolving
fish.
I had this pin on several
years ago at a conference.
And the physicist, Murray
Gell-Mann was there.
And he's a very
learned gentleman.
And he said, Dan,
I like your pin.
He said, do you know
that the Christian fish
symbol was the first acronym?
Ichthus.
That's what you see
there in the middle,
ichthus is the
Greek word for fish.
And it stood for
[SPEAKING GREEK].
Jesus Christ, God,
Son, and Savior.
That's why they use the fish.
I said, that's very nice,
Murray, really interesting.
He said, what I want
to know, Dan, is,
what does D-A-R-W-I-N stand for?
I thought, that's a
very good question.
Well I'm not really
a classical scholar.
But I did take Latin in
high school for a while.
I thought, let me
work on that and see
what I can come up with.
So I went off and had a cup of
coffee, and got out my pencil
and worked at it for a while.
And I came up with something
which seems to fit pretty well.
So here we go.
Here's D-A-R-W-I-N. There's no
W in Latin so you have to use
double U. OK?
Delere auctorem rerum ut
universum infinitum noscas.
Destroy or delete the
author of things in order
to understand the
infinite universe.
Thank you for your attention.
Dr. Dennett will be happy
to answer your questions.
If we can see anybody.
If we can see anyone, yes.
May we have the lights up?
There we go.
Right here.
I know you've had a number
of constructive debates
with Dreyfus, Hubert Dreyfus.
Do you consider him a skyhook
proponent or something else?
I'm sort of curious where
he would stand in there.
Thank you.
Yeah.
Hubert Dreyfus at Berkeley,
a phenomenologist,
good philosopher,
longtime critic
of artificial intelligence.
Yes, I would call him
a mind creationist,
because he has supposed
that it was in principle
impossible to build up
from the Turing base
to a mind with creativity
and intelligence.
He thinks that the sort of
insight that human minds have
is beyond the scope of
not just current AI,
but any imaginable AI.
That makes him a
mind creationist.
He thinks of mind as a skyhook.
We thought until
about 18 months ago
that we had evolved some very
impressive economic structures,
which went crashing
and burning since then.
Is that an evolution
that went wrong?
Evolution doesn't
guarantee success.
After all, think of it this way.
Something like 99% of the
species that have ever existed
are now extinct.
But here's a more hopeful
way of thinking of it.
99% or more, much more
than 99%, of all the things
that have ever lived
have died childless.
But not a single one
of your ancestors did.
Think of how lucky
that makes you.
You sit at the end of an
incredibly lucky strain that
goes back three and
a half billion years
without a single ancestor
that died childless.
Dr. Dennett, you talked
about things-- culture
such as tonal
music and religion,
poetry, even
earworms, things which
have universal appeal among
all cultures, but apparently
no reasonable basis for
them at all that I can tell.
I mean, there is a
theory which attempts
to explain the universality, the
compellingness, of such things
by describing them as an
artifact of the evolution
of consciousness,
a theory which says
that consciousness itself
is a product of memes
rather than vice versa.
And I'm talking about The
Theory of the Bicameral Mind
By Dr. Julian James.
I wonder if you'd
comment on that.
Yeah.
First of all, I got a lot
of good ideas from Julian.
And I hope I've given
him credit along the way.
I'm a fan of that book too.
But I think Julian James
book is a classic book.
It's also a sort
of cult classic,
because it has some
wonderful ideas
and it has some ideas that
I think are just daft.
And I don't think
James could tell
the difference between them.
But that's like a lot of
other creative geniuses.
So I have been happy to mime
his work for good insights
over the years.
And in my own theory of
consciousness, which you also
sort of described
right there, I've
drawn heavily on some of those.
But let me quickly say
something about your point about
whether there's any basis
for the survival of memes.
To me, the single
most important gift
of the memetic perspective
when we look at culture
is that it acknowledges
and it helps
us to see that cultural items
can persist not because they're
good for us, not because they're
true, not because they're
wonderful, but just because they
can replicate in our brains.
Now many replicate in our brains
because they're wonderful.
And those are the ones
that we particularly
seek out, and domesticate,
and try to foster.
Of course we're not always
very good judges of that.
But it's very
important to remember
that some cultural items
have their own fitness,
independently of our fitness.
When I was working on my
book on religion and people
were learning that I was looking
at the evolution of religion
and of religious memes, a lot
of people said to me, oh, Dan.
That's really interesting.
What do you think
religions are for?
After all, every
human group that's
ever been looked at closely has
religion of some form or other.
It's got to be good
for something, right?
And I said, no.
Not necessarily.
It might be, but
not necessarily.
Every human group
that's ever been studied
has the common cold.
What's that good for?
It's good for itself.
It replicates because it can.
It has its own fitness.
And so do memes.
Now many memes
have their fitness,
as it were, in spite of our
efforts to eradicate them
or in spite of the fact
that we don't care for them.
Others have their fitness
because we treasure them
dearly, rightly or wrongly.
If you want to have a good
theory of cultural evolution,
which I very much
want, you should
start with a level
playing field, which
says we need to explain
the fitness of memes
in their own terms first.
And then we can see which
of them are, if you like,
mutualists, which ones of
them are beneficial to us,
and which of them are parasites
and are not beneficial to us.
Both are possible.
This masterful lecture
this evening was the end,
at this point-- it's
going on, of course--
of 50 years of fighting
the creationists.
And I think we all should
get down on our knees
and thank God for
the creationists,
because they forced us to
get our stuff together.
Thank you, sir.
Yes, Professor.
I was thinking about three
constants-- time, sleep,
and memory-- and how
they are combined.
Also I'd like to make an
inquiry into time machines.
Is memory a time machine,
a simplistic form
of a time machine?
And in speaking of
space time, that time,
does time have memory?
Well I'm just going to
take part of that, the part
that I'm sure I understand.
What I like to say is
that the job of brains
is to produce future,
to produce expectations.
And they do this by mining
the past and the present,
and then turning that ore into
expectations about the future.
Brains are anticipation makers.
That's why we've got them.
And our brains, we can
look farther and better
into the future than
any other species.
We can conceive of
events that will
happen long after we are dead.
We can conceive of events that
happen all over the universe.
We're the only species
that can do this.
But every species
has a brain, the job
of which it is to extract
information from the world
and use it to better anticipate
what's going to happen next.
So there is a deep
relationship between memory,
and expectation, and mind.
I think it's fascinating to
hear about all these processes
that go on in our brain.
And I can almost visualize
these neurons firing like crazy
to each other.
But why do we actually have to
have the sensation of thinking?
And what is it actually?
And what is really good for?
I think one of the philosophers,
one of your colleagues,
once stated, why
aren't we all zombies?
Well there's no short answer
to your question except this--
we are all zombies.
That is to say,
we, and we alone,
are creatures who
are equipped when
asked to talk about what
we've been thinking about.
Penny for your
thoughts, somebody says.
And we can answer.
We are the kind of being that,
because we have language,
is able to access some small
subset of the processes that
are going on in our
brains, those neural
processes you speak of.
But when we do access them,
our capacities to verbalize
have to be run through a
sort of metaphorical sieve
so that we can only speak in
sort of unconscious metaphor
about the processes actually
going on in our brain.
But we can do that.
And that, sir, is
what consciousness is.
[INAUDIBLE]
I don't know.
I think we will
call it quits here
and thank Dr. Dennett
for a wonderful talk.
If you should happen to come
here at this time next week,
you'll be surprised that
there isn't another talk.
Instead there is a
Beethoven concert
with the [INAUDIBLE] Symphony
and the [INAUDIBLE] Piano
Concerto.
But Dr. [INAUDIBLE] will be
talking the following week.
So please write it
on your calendars.
She will be talking about
observing the brain at work,
seeing those neurons
firing, and starting
on the process of trying to
understand how we actually
go about thinking.
So I'd not only like to thank
Dr. Dennett again, but also
Dr. Taylor for coming
here to introduce him.
Thank you.
