The Fruitful Facets of Galton's Polyhedron 445
the orthogenetic school. He even slipped into the philosophic fallacy that Whitman
criticized (see p. 385), by equating nonisotropy with teleology in the strong sense
of inherently unscientific assertion: "According to the Darwinian principle, species
forming variability—mutability—does not take place in definite directions.
According to that theory, deviations take place in almost every direction without
preference for any particular one, and especially without preference for that
direction along which differentiation happens to be proceeding. Every hypothesis
which differs from Darwin's in this respect must be rejected as teleological and
unscientific" (1909a, volume 1, p. 198).
In a later, remarkable passage, de Vries gathered all these elements together,
identifying nonisotropy as both a central Darwinian claim and a necessary bulwark
in the struggle against supernaturalism. He also acknowledges that Darwin applied
the resulting selectionist mechanism at the organismal level, whereas he favors the
species level, thus devising a fundamentally different theory:
We are strongly opposed to the concept of a definite "tendency to vary"
which would bring about useful changes, or at least favor their appearance.
The great service, which Darwin did, was that he demonstrated the
possibility of accounting for the evolution of the whole animal and
vegetable kingdom without invoking the aid of supernatural agencies.
According to him, species forming variability exists without any reference
to the fitness of the forms to which it gives rise. It simply provides material
for natural selection to operate on. And whether this selection takes place
between individuals, as Darwin and Wallace thought, or whether it decides
between the existence of whole species, as I think; it is the possibility of
existence under given external conditions which determines whether a new
form shall survive or not... The mutability of Oenothera Lamarckiana
satisfies all these theoretical conditions perfectly. Nearly all organs and all
characters mutate, and in almost every conceivable direction and
combination (1909a, volume 1, p. 257).I have presented this extended treatment of de Vries for a reason embedded in
the plan of this chapter, and crucial to the logic of this book. I argue that
"internalism" poses two separate challenges to pure Darwinian functionalism:
saltational change arising from internal forces of mutability, and inherent
directionality of variation (corresponding to facet-flipping and channeling on
Galton's polyhedron). Most internalists ("structuralists," "formalists," "laws of
form" theorists in other terminologies) emphasize the second theme of channels
and preferred directionality of variation (now most often expressed in the
popularity of "constraints" as a subject in modern evolutionary literature—see
Chapters 10 and 11). This style of internalism represents the primary theme of
Goethe, of Geoffroy, of Owen, and of the orthogeneticists. Fewer internalists
emphasize the saltational theme—and those who do, like Bateson, tend to support
channeling as well as facet flipping