The Structure of Evolutionary Theory

CHAPTER EIGHT

Species as Individuals in the

Hierarchical Theory of Selection

The Evolutionary Definition of Individuality

AN INDIVIDUALISTIC PROLEGOMENON

The perceived excesses of the French Revolution may have sapped English
enthusiasm for the tenets of Enlightenment Rationalism—the faith of Darwin's
grandfather Erasmus. The subsequent romantic movement stressed opposite
themes of emotion vs. logic, and national variety vs. universal reason. Charles
Darwin, who revered his grandfather but also loved Wordsworth's poetry, received
a firm grounding in both great philosophical and aesthetic traditions. He also—and
perhaps as a direct result—maintained strong fascination for a central theme
common to both movements, but for different reasons: the role of individuals as
agents of change in larger systems. (The Enlightenment focussed on individuals as
effective intellectual agents and inherent bearers of rights—"unalienable" in
Jefferson's memorable phrase—and therefore as primary causal and moral agents
in themselves, not as expendable items of a larger collectivity. The Romantics
exalted individual effort as the motive force of social change through the actions of
occasional heroes of higher sensibility.)
In any case, and whatever the deeper source, we do know that, as Darwin
stitched together his theory of natural selection in 1838, he centered his major
intellectual struggle in the few weeks before his "Malthusian" insight (Schweber,
1977) upon the role of individuals as primary causal agents of evolutionary pattern,
even at largest scales (see full discussion in Chapter 2). He first studied the
economic theory of Adam Smith through the major secondary source then
available—Dugald Stewart's On the Life and Writing of Adam Smith. He expressed
special fascination for Smith's distinctive notion that the overall optimality of an
economy might best (and paradoxically) is fostered by allowing individuals to
maximize personal profit without restraint (the doctrine known ever since as
laissez faire, or "let do"—more roughly, "leave 'em alone"). He then read an
extensive analysis of the work of the great Belgian statistician Adolphe Quetelet—
particularly his central notion of I'homme moyen (average man), based on the
aggregation of individual attributes into collectivities.

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