Seeds of Hierarchy 223
EXPANSION OF THE HIERARCHY BOTH UP AND DOWN FROM A DARWINIAN FOCUS
ON ORGANISMS. Weismann devised germinal selection as an ad hoc hypothesis to
resolve his longstanding embarrassment over the problem of degeneration. In
18 96, he applied selection throughout Haeckel's hierarchy of "individuals,"
extending from cell constitutents to clonal colonies (1896, p. 42), and recognizing
three primary levels—Darwin's conventional struggle for existence among
organisms, Roux's histonal selection, and his own germinal selection.
But by 1903, in a statement that I regard as wonderfully prophetic of current
concerns, Weismann had proceeded beyond his immediate theoretical needs to full
generality. He had used germinal selection to break through the Allmacht of
exclusivity for Darwin's level. But now he recognized the inexorable logic of a
fully developed and extended theory of hierarchy—reaching right up to species
selection at the top.
I have called these processes which are ceaselessly going on within the
germ-plasm, Germinal Selection, because they are analogous to those
processes of selection which we already know in connection with the larger
vital units, cells, cell-groups and persons. If the germ-plasm be a system of
determinants, then the same laws of struggle for existence in regard to food
and multiplication must hold sway among its parts which hold sway
between all systems of vital units—among the biophors which form the
protoplasm of the cell-body, among the cells of tissue, among the tissues of
an organ, among the organs themselves, as well as among the individuals of
a species and between species which compete with one another (1903, vol.
2, p. 119).If Weismann had presented this full elaboration of hierarchy only as a foot-
note, a flash of insight in a book devoted to other goals, I could not claim him as an
intellectual forebear of our modern excitement. Good ideas originate in fair
abundance, and we must look to development and application for our main criteria
of sustained scientific worth. If Weismann had even devoted an isolated chapter to
hierarchy, I would note his insight with praise, but grant him limited success for
failing to recognize the power of this theme as an organizing framework for
evolutionary mechanisms. But, in fact, Weismann did fully grasp the fundamental
difference between classical Darwinism and the expanded theory of interacting
levels of selection—and he regarded his exposition of hierarchy as both the central
feature of his mature thinking, and the unifying concept of all evolution: "This
extension of the principle of selection to all grades of vital units is the
characteristic feature of my theories; it is to this idea that these lectures lead, and it
is this—in my own opinion—which gives this book its importance. This idea will
endure even if everything else in the book should prove transient" (1903, in
preface, vol. 1, p. ix).
How ironic that a man who so explicitly promoted the centrality of hierarchy
should be remembered today primarily for his earlier advocacy of Allmacht at the
traditional level of organismal struggle alone! A study of Weismann's intellectual
ontogeny should lead us to respect the logic and power of hierarchy, whatever our