Is Biology Messy?

To the Editors:

I am grateful to Richard Lewontin for including my book Making Sense of Life in his very interesting recent essay review, “The Truth About DNA” [NYR, May 1]. At the same time, however, I would like to correct some errors in his representation of both my intent and my argument:

1. I do not take developmental biology as an example of an “epistemological culture,” but rather as a subject that exposes marked differences in the kinds of explanations, coming from different epistemological cultures, that have been offered over the course of the last century.

2. Lewontin rightly attributes to me a skepticism about our ever reaching a unified or complete explanation of biological development. But why should such skepticism be seen as a “negative view”? Is it a priori evident that a unified explanation is better, or more positive, than a pluralistic one? Not to me.

3. I included the model of insect segmentation by von Dassow et al. precisely in order to illustrate the value of “cum-bersome, messy, and…opaque” models, and as a clear contrast with those models that have traditionally been valued (at least by those coming from the mathe-matical sciences) for their streamlined elegance.

4. In much the same spirit, my discussion of Rashevsky and Turing was not intended to illustrate the virtues of simplicity and elegance, but if anything, the ultimate inadequacy of such ideals for biological systems.

Evelyn Fox Keller
Program in Science, Technology, and Society
MIT Center for Philosophy of Science University of Minnesota Minneapolis, Minnesota

Richard Lewontin replies:

It is instructive and humbling for a reviewer who thinks he knows how to write to be called to account for rhetorical failures. I have no quarrel with Evelyn Keller’s description of her intent in Making Sense of Life. To speak directly to her points:

1. I wrote carelessly of the epistemological culture of developmental biologists. I did not mean that developmental biology is itself an epistemological culture, which makes no sense. Within the community of developmental biology there are those who believe that the proper goal of knowledge in that field is the detailed description of the immensely complex chain of molecular mechanisms that result in development of particular features of organisms, while others, in a tradition that goes back a century, think that the proper goal of the field is the discovery of a few overarching principles and, possibly, their formal description in mathematical terms.

2. My reference to Keller’s “negative view” of a unified theory of biology was in no way meant to imply that she places a higher value on one kind of explanation than on another. Her view is negative in the simple sense that she characterizes the attempt to create a unified theory as having failed up till now. If we have any disagreement, it is that I believe that failure to be inevitable.

3. I confess a continuing difficulty in understanding how a model described by her as “cumbersome, messy, and…opaque” and that would not work for any biologically reasonable parameters nevertheless has a “value,” unless it is to warn people off.

4. I did not intend to suggest that Keller’s discussion of the Rashevsky school and Alan Turing’s work was meant to illustrate the virtues of simplicity and elegance, except in the minds of those people. Keller and I agree that biology is inherently messy.