Seeds of Hierarchy 197
Lamarck's system (as produced by the different mechanism of natural selection).
Lamarck's hierarchical theory set a context (in opposition) for Darwin's
distinctive single-level theory of extrapolation, based on uniformitarian
assumptions, from the palpable and small-scale cases of adaptation that surround
us to all evolutionary changes at all scales of time and magnitude. Natural selection
does not emerge from the raw observation of nature, but as a complex idea
embedded both in observation and in Darwin's voracious study and trenchant
analysis of contemporary ideas in biology and general culture. Lamarck's
hierarchical theory formed an important, though not widely recognized, part of the
mix, distilled by Darwin to extract a theory that would change the world.
Darwin directed his anti-hierarchical theory against Lamarck's old and invalid
concept of hierarchy—different and opposed causes at distinct levels. Darwin
labored mightily to encompass the entire domain of evolutionary causation within
a single level—natural selection working on organisms. He knew what he wanted
to do, and he pursued and extended the logic of his argument relentlessly. Most of
his supporters (including Wallace and Huxley) never understood the subtle logic of
the single-level theory. Among the few who did, Weismann also made a strenuous
effort to bring the system to completion. I find the strongest historical support for
modern versions of hierarchy (same causes working in different ways at various
levels, in direct contrast with Lamarck's notion of disparate causes in opposition),
in the intense intellectual struggle carried out by the two greatest selectionists of
the 19th century—Weismann for lower levels, and Darwin himself for upper
levels— to bring the nonhierarchical theory of selection to completion and
sufficiency. Both men, as we shall see in the subsequent sections of this chapter,
struggled valiantly, but could not prevail. (Chapter 5 will then discuss (in the
saltationist context of his version) the other major hierarchical system of evolu-
tionary thought before the Modern Synthesis—the fascinating and subtle early 20th
century theory of de Vries on reintroducing selection at the species level after
denying its central importance at Darwin's own level of the organism.) Call it the
bad penny that keeps cropping up, or the pearl of great price always found within,
but hierarchy seems unavoidable. Could the basic reason for this persistence find
an explanation in something so lovely, and so beautifully simple, as truth-value?
No Allmacht without Hierarchy: Weismann
on Germinal Selection
THE ALLMACHT OF SELECTIONIn 1893, Herbert Spencer, who had a word (many of them) and a thought for nearly
everything, * published a long critique in the Contemporary Review—
*Spencer's star has fallen dramatically. He was once renowned as a polymathic
philosopher; he is now generally regarded as an unread eminent Victorian with acute
logorrhea.