comparison with a discrete building that continually grew but did not change its
location or basic function), then how shall we conceive "the structure of
evolutionary theory" (chosen, in large measure, as the title for this book because I
wanted to address, at least in practical terms, this central question in the history
and content of science)? Shall we accept Darwin's triumphalist stance and hold that
the framework remains basically fixed, with all visually substantial change
analogous to the non-structural, and literally superficial, icing of topmost
pinnacles? Or shall we embrace Falconer's richer and more critical, but still fully
positive, concept of a structure that has changed in radi-
1 - 2. The "wedding cake" pinnacles that festoon the top of Milan Cathedral, and that were
not built until the first years of the 19th century after Napoleon
conquered the city.6 THE STRUCTURE OF EVOLUTIONARY THEORY