Richard Lewontin: A topic that I would like to see discussed
is ideology. I think it's very important.
John Beatty: Could you give us a hypothesis about the way
that ideology enters in?
Lewontin: Well, I think there are people committed to—and
more now than ever—to an optimality view of evolution, to
a functional view that everything is the best of all possible worlds.
And that has a powerful effect on views of neutrality.
Ford Doolittle: Genomics is based on that view. There's
lots of money dependent on a hyperadaptationist view. I think this
naturally segues into a discussion of neutrality, optimality, function
at all different levels. It has never received rigorous, philosophical
attention.
Beatty: I think I see where you're going, but just to clarify,
can you articulate the way in which optimality represents an interest
of people who have particular positions in these debates, or how
optimality represents an interest within genomics?
Doolittle: We were discussing it earlier in connection with
junk DNA. Do organisms with four times as much DNA need four times
as much DNA? Were introns really introduced in order to increase
the flexibility of evolution? There are many levels of selection
involved here. I believe introns do increase the flexibility of
evolution, but I don't believe that they were introduced into a
population because they would have that effect. These things are
not discussed carefully, theoretically, but they are always the
subtext of what we do, and particularly in molecular evolution.
This is certainly the case in the evolution of molecules; for example,
in the case of RNA editing, which I think is junk piled on top of
junk, ratcheting itself to inevitability. But many molecular biologists
believe that selection created this wonderful stuff. There is a
very strong selectionist, panadaptationist view of molecular biology
and genomics. There are millions of dollars to sequence genomes,
and of course they don't like to hear that most of that is really
junk. There was an article in the last issue of Science
to the effect that, maybe all those insertion sequences are really
there for a purpose. It's very mystical.
James Crow: I've always found it really surprising that
molecular biologists can be such panselectionists, though I don't
mean to tarnish the whole field.
Doolittle: But at the same time they accept neutrality at
the molecular sequence level, and always have. So it's very interesting.
William Provine: There is an element that goes with ideology,
namely, aesthetics. The really beautiful things are deeply attractive
to practically everyone. Kimura hated the idea that his beautiful
neutral theory would have to be modified to nearly neutral. He hated
it. He resisted it.
Lewontin: Because it wasn't clean, you mean?
Provine: Not clean at all! It doesn't have that ??? to it.
He wanted it to be beautiful. And when he was able, he did it. In
the 1983 book, he's got a horribly complex gamma distribution version
of the nearly neutral theory, and he's got the completely neutral
theory. Two years later, with the DNA sequence data, he's gone back
to his completely neutral model. And is he happy with that? His
papers just exude happiness in 1985 and 86 because he's
back where he wanted to be. And he's confident. It's beautiful to
see it. And this is an aesthetic preference.
Lewontin: Would you accept an amendment? The word "aesthetic"
bothers me a little. I think it's a little different. To call it
"aesthetic" removes it from an historical perspective.
The ideal that I was taught as a high school student of what a science
is, and that Motoo learned, and that we all learned [pounds table]—who
embodied that ideal?
George Smith: [immediately] Newton.
Lewontin: That is to say, the more general, the more neat,
the more succinct the law is, the greater the science, and we're
all trying to be Newtons. Motoo was trying to be the Newton of biology
and evolution. And if you have to say, "No, it's not so simple;
look at the second volume of the Principia instead of the
first volume, where Newton says that there are real objects moving
in a fluid, and there's friction, and it really doesn't work the
way the first law says"—you know—that's biology.
So I think that it's not an aesthetic issue, but an issue of the
formation of intellectuals in the natural sciences, that the ideal
is to have it all be...
Crow: [finishing Lewontin's sentence] simple. It's simplicity
rather than aesthetics.
Provine: Kimura was intensely aware of Fisher's attempt
to go from laws of gases to natural selection.
Lewontin: But that's not aesthetics. Who is the greatest
scientist who ever lived, who made a generalization that applies
to everything?
Michael Dietrich: But when Gillespie states the selectionist
challenge, he puts it in aesthetic terms. He says the big challenge
is to produce a selectionist theory that is "as elegant"
mathematically.
Lewontin: But don't call it "aesthetic," because
that suggests the origin of it outside of a very important cultural
historical phenomenon, which is the training of scientists and the
ideological formation of scientists with regard to what it is to
be a scientist. I think that's the issue.
Provine: I would still argue that aesthetics is important....
For the generation of hypotheses, I think aesthetics is incredibly
important. But when it's used to discriminate between hypotheses,
it falls on its butt. That's where aesthetics has a real problem.
But in the generation of theories, I would still argue that there
is an element of beauty that people do care about.
Smith: [Smith is a Newton scholar] I'm tempted to make a
comment about Newton, but maybe it's best if I didn't.
Lewontin: It's the ideal Newton we're interested in. [laughter]
Beatty: Yeah, what Newton really said is unimportant. [laughter]
Smith: Newton, before he started writing the Principia,
was convinced that the actual motions of the planets were beyond
human reckoning. And what he saw was that this simple tool could
allow further investigation, and that that further investigation
could then complicate the initial theory in a way that would be
empirically driven rather than a matter of mere hypothesis. So it's
a very sophisticated picture of why simplicity is good, because
it's going to promote more effective empirical inquiry over the
long run.
Beatty: We've talked about a number of different reasons
why people were attracted to the neutral theory: partly because
it was Newtonian, or because it was elegant. Other people have used
the term "tractability" to refer to kind of the same thing.
Maybe we can talk about all these as "extra-empirical"
factors that help explain why people were attracted to the neutral
theory. But I would like for Dick to say something about what he
meant by "ideological" commitments to natural selection
and optimality. Ford cashed it out in terms of the value of genomics
depending on not everything being junk DNA—he even mentioned
the monetary value of the field.
Lewontin: I'm not sure any more. I once would have said
that those different ideologies came out of social and political
worldviews. But I'm no longer convinced of that. I wouldn't want
to defend that claim. I would want to defend the claim that there
are persons for whom it does come down to that. But it seems to
me not true that one should attempt that reduction. I think when
I look around at commitments to optimality, for instance, I see
they cover a lot of people and territories that have no obvious
connection. So, for the foolishness of my youth, I'm not responsible.
But it's still ideological. I don't want to restrict the term "ideology"
to politics.
[For an example of Lewontin's earlier view, see this 1973
video clip]
Crow: You know, Haldane insisted that Marxist philosophy
had a great influence on his science, but I'm not sure that it did.
Lewontin: No, and in fact the last speech that he gave,
at the last Congress of Genetics in the Hague, was the most un-Marxist,
reactionary piece I've ever heard.
Dietrich: Dick, in your 1974
book, you talk about how ideology functions
.
Lewontin: Let me repeat my simplistic view of the life of
Dobzhansky. Dobzhansky started out life studying beetles in central
Asia. He was incredibly impressed with their diversity: more than
he could cope with. And his whole life was devoted to the claim
that, not only was there a tremendous amount of diversity in populations,
but that that diversity was a good thing. And he said over and over
and over again that diversity per se is adaptive and good. And he
and I used to have terrible fights about that. That's what I would
call "scientific ideology." His whole life was informed
by the view that polymorphism in the broadest sense was a virtue,
and the problem with inbred populations was that they were all uniform.
There are all those papers on how homozygotes are "narrow specialists"
and heterozygotes are "broad generalists." He even argued
that the worst thing in the world was not to be homeostatic. You
want to be homeostatic, which means that you don't want to respond
too much to the environment. So I used to say to Dobzhansky, "That's
crazy, because on your conception of homeostasis, an unconditional
lethal is the most homeostatic genotype there is. Because irrespective
of the environment, it always shows the same phenotype, namely it's
dead." And he would say, "Oh this fellow Lewontin is crazy.
He thinks that lethals are homeostatic." And that wasn't the
point.
Dietrich: In your book you say that ideology drives the
controversy and prevents resolution.
Lewontin: Well, I'll stick to that.
Beatty: Maybe one way to pose the question about ideology
in the neutralist-selectionist controversies is to contrast those
controversies, just for the sake of discussion, with the classical-balance
controversy. Because among the multiple sources of the neutralist-selectionist
debate is probably the classical-balance debate, in which, I think
a lot of people would agree, ideology played a role.
Lewontin: Although in very subtle ways, John. For example,
the last time I had a fight with Dobzhansky, just before he died,
I accused him of being a biological determinist. And he hated that.
I said "You're as much of a biological determinist as Hermann
Muller was. It's just that you think the heterozygotes are the most
wonderful thing, and he thinks the homozygotes are." But they
were both biological determinists. And I think that was a supervening
ideology.
Crow: And if we hadn't had this debate about nuclear testing
going on, it probably would have been a different kind of debate,
I think. So it really was political in a very ordinary sense.
Lewontin: I think that's also very interesting.
Beatty: So my question is, could a debate that had such
a rich ideological, social and political context be the source of
a debate that has no ideological, social and political context?
Crow and Lewontin: Good question.
Beatty: It's not at all apparent to me what the social context
of the neutralist-selectionist controversy is. They seem highly
technical. But maybe it's just because I've been living through
them, and it's hard to see where you're coming from when you're
there.
Lewontin: It might be more a question of who takes up one
side or the other.
Jan Sapp: Back to this word "ideology." Within
the neutralist-selectionist debate, we certainly can see an ideology
of "disciplinary interests." As Mike Dietrich talks about,
the disciplinary interests of those working at the macro scales
had different interests than those working at the molecular levels.
Take, for example, the interests of Mayr and Simpson and Dobzhansky
to protect the theories of the synthesis. To put it another way,
if molecular evolutionists were not neutralists, there would still
have been a controversy. The fact that they were neutralists just
exacerbates the controversy. It's an issue of interlopers, the molecular
biologists, changing the direction of evolutionary biology and the
way in which one does biology. And I think these are matter of—I
don't know—ideology, in the sense that they involve disciplinary
interests and social interests.
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