Free The Panda’s Thumb by Stephen Jay Gould

only arithmetically, thus guaranteeing an intense struggle for existence. In fact, Darwin had read the Malthusian statement several times before; but only now was he prepared to appreciate its significance. Thus, he did not turn to Malthus by accident, and he already knew what it contained. His “amusement,” we must assume, consisted only in a desire to read in its original formulation the familiar statement that had so impressed him in Quetelet’s secondary account.
    In reading Schweber’s detailed account of the moments preceding Darwin’s formulation of natural selection, I was particularly struck by the absence of deciding influence from his own field of biology. The immediate precipitators were a social scientist, an economist, and a statistician. If genius has any common denominator, I would propose breadth of interest and the ability to construct fruitful analogies between fields.
    In fact, I believe that the theory of natural selection should be viewed as an extended analogy—whether conscious or unconscious on Darwin’s part I do not know—to the laissez faire economics of Adam Smith. The essence of Smith’s argument is a paradox of sorts: if you want an ordered economy providing maximal benefits to all, then let individuals compete and struggle for their own advantages. The result, after appropriate sorting and elimination of the inefficient, will be a stable and harmonious polity. Apparent order arises naturally from the struggle among individuals, not from predestined principles or higher control. Dugald Stewart epitomized Smith’s system in the book Darwin read:
    The most effective plan for advancing a people…is by allowing every man, as long as he observes the rules of justice, to pursue his own interest in his own way, and to bring both his industry and his capital into the freest competition with those of his fellow citizens. Every system of policy which endeavors…to draw towards a particular species of industry a greater share of the capital of the society than would naturally go to it…is, in reality, subversive of the great purpose which it means to promote.
    As Schweber states: “The Scottish analysis of society contends that the combined effect of individual actions results in the institutions upon which society is based, and that such a society is a stable and evolving one and functions without a designing and directing mind.”
    We know that Darwin’s uniqueness does not reside in his support for the idea of evolution—scores of scientists had preceded him in this. His special contribution rests upon his documentation and upon the novel character of his theory about how evolution operates. Previous evolutionists had proposed unworkable schemes based on internal perfecting tendencies and inherent directions. Darwin advocated a natural and testable theory based on immediate interaction among individuals (his opponents considered it heartlessly mechanistic). The theory of natural selection is a creative transfer to biology of Adam Smith’s basic argument for a rational economy: the balance and order of nature does not arise from a higher, external (divine) control, or from the existence of laws operating directly upon the whole, but from struggle among individuals for their own benefits (in modern terms, for the transmission of their genes to future generations through differential success in reproduction).
    Many people are distressed to hear such an argument. Does it not compromise the integrity of science if some of its primary conclusions originate by analogy from contemporary politics and culture rather than from data of the discipline itself? In a famous letter to Engels, Karl Marx identified the similarities between natural selection and the English social scene:
    It is remarkable how Darwin recognizes among beasts and plants his English society with its division of labor, competition, opening up of new markets,