136 THE STRUCTURE OF EVOLUTIONARY THEORY
tactic closely follows his argument about human morality, and therefore
emphasizes his extreme reluctance to embrace supraorganismal selection, and his
almost desperate effort to confine explanation to the organismal mode. The
recognition that Darwin, despite such strong reluctance, could not avoid some role
for species selection, builds a strong historical argument for the ineluctability of a
hierarchical theory of selection. (I shall show in Chapter 3 that none of the few
19th century scientists who truly grasped the full range and subtlety of selectionist
theory could avoid important roles for levels other than the organismic.)
As with the next topic of creativity for natural selection (pp. 137-159), the
issue of levels in selection has resounded through the entire history of evolutionary
theory, and continues to set a major part of the agenda for modern debate—as it
must, for the subject lies (with only a few others) at the very heart of Darwinian
logic. Wallace never comprehended the question of levels at all, as he searched for
adaptation wherever he could find it, oblivious to any problems raised by the locus
of its action; Kropotkin, in asserting mutual aid, never grasped the problem either;
Weismann shared Darwin's insight about the problem's fundamental nature, but
also came to understand, after a long and explicit intellectual struggle with his own
strong reluctance, that exclusivity must yield to hierarchy (pp. 197-224).
In our generation, Wynne-Edwards (1962) riled an entire profession by
defending the classical form of group selection as a generality, while Williams
(1966) penned a powerful rebuttal, urging us all to toe the Darwinian line (see
Chapter 7 for a full account). The classical ethologists invoked various forms of
group selection (often by default); the sociobiologists proclaimed a revolution by
reaction and return to the pure Darwinism of individual advantage. Dawkins
(1976) attempted an even stronger reduction to exclusivity for genie selection, but
his false argument rests on a confusion of bookkeeping with causality, and his own
later work (1982) negates his original claim, though Dawkins seems unaware of his
own contradictions (see Chapter 8). Supporters of hierarchy theory—I am one, and
this is a partisan book—are revising Darwinism into a multilevel theory of
selection.
This issue will not go away, and must excite both interest and passion.
Nothing else lies so close to the raw nerve of Darwin's radicalism. The exclusivity
of organismal selection, after all, provides the punch line that allowed the vision of
Adam Smith to destroy the explicit beauty and harmony of William Paley's world.
Viewed in this light, the Origin's very few statements about solace become
particularly revealing. Darwin had just overturned a system that provided the
philosophical basis of human comfort for millennia. What could he supply in
return, as we continue to yearn for solace in this vale of tears? One might be
tempted to read the few Darwinian statements about solace as peculiar,
exceptional, even "soft" or illogical. But we should note another feature of these
statements as well: they yield no ground whatever on the key issue of organismal
struggle. Solace must be found in other guises; the linchpin of selection as struggle
among organisms cannot be compromised.