cal ways by incorporating entirely different styles into crucial parts of the building
(even the front entrance!), while still managing to integrate all the differences into
a coherent and functional whole, encompassing more and more territory in its
continuing enlargement?
Darwin's version remains Gothic, and basically unchanged beyond the visual
equivalent of lip service. Falconer's version retains the Gothic base as a positive
constraint and director, but then branches out into novel forms that mesh with the
base but convert the growing structure into a new entity, largely defined by the
outlines of its history. (Note that no one has suggested the third alternative, often
the fate of cathedrals—destruction, either total or, partial, followed by a new
building of contrary or oppositional form, erected over a different foundation.)
In order to enter such a discourse about "the structure of evolutionary theory"
at all, we must accept the validity, or at least the intellectual coherence and
potential definability, of some key postulates and assumptions that are often not
spelled out at all (especially by scientists supposedly engaged in the work), and
are, moreover, not always granted this form of intelligibility by philosophers and
social critics who do engage such questions explicitly. Most importantly, I must be
able to describe a construct like "evolutionary theory" as a genuine "thing"—an
entity with discrete boundaries and a definable history—especially if I want to
"cash out," as more than a confusingly poetic image, an analogy to the indubitable
bricks and mortar of a cathedral.
In particular, and to formulate the general problem in terms of the specific
example needed to justify the existence of this book, can "Darwinism" or
"Darwinian theory" be treated as an entity with defining properties of "anatomical
form" that permit us to specify a beginning and, most crucially for the analysis I
wish to pursue, to judge the subsequent history of Darwinism with enough rigor to
evaluate successes, failures and, especially, the degree and character of alterations?
This book asserts, as its key premise and one long argument, that such an
understanding of modern evolutionary theory places the subject in a particularly
"happy" intellectual status—with the central core of Darwinian logic sufficiently
intact to maintain continuity as the centerpiece of the entire field, but with enough
important changes (to all major branches extending from this core) to alter the
structure of evolutionary theory into something truly different by expansion,
addition, and redefinition. In short, "The structure of evolutionary theory"
combines enough stability for coherence with enough change to keep any keen
mind in a perpetual mode of search and challenge.
The distinction between Falconer's and Darwin's predictions, a key ingredient
in my analysis, rests upon our ability to define the central features of Darwinism
(its autapomorphies, if you will), so that we may then discern whether the extent of
alteration in our modern understanding of evolutionary mechanisms and causes
remains within the central logic of this Darwinian foundation, or has now changed
so profoundly that, by any fair criterion in vernacular understanding of language,
or by any more formal account of departure from original premises, our current
explanatory theory must be de-
Defining and Revising the Structure of Evolutionary Theory 7