Conceptual Change and the Rhetoric of Evolutionary Theory: ‘Force Talk’ as a Case Study and Challenge for Science Pedagogy

Abstract

Darwinian theories vary. Some of the variation consists in differences in conceptual frames. These identify the entities and processes over which natural selection ranges. Different conceptual schemes are most easily identifiable by the different images, similes, analogies, and metaphors—in general, tropes—by which evolutionary theories are brought to bear on particulars. I show how Darwin’s metaphors balanced function, chance, and determinism in living things by seeing artificial selection in terms of natural forces and natural forces in terms of artificial selection. I then argue that the Modern Evolutionary Synthesis highlighted Darwin’s view of natural selection as a creative process, which earlier Darwinians had abandoned, by shifting to a conceptual framework and family of tropes that made images of force and design recessive. With the use of mathematical game theory to model gene frequency changes in the 1970s, however, design and force metaphors became dominant again, with the unintended result that images of Darwinism as promoting a god-abandoned, dog-eat-dog that had lodged deeply in popular culture long ago, were reawakened. Analysis of evolutionary discourse that hopes to reach students and the public must attend closely to the uses and abuses of conceptual tropes, ‘force’ and ‘design’ among them. This poses a question for pedagogy. How well can one teach evolutionary science without teaching some of its conceptual, and hence its rhetorical, history? Will students perceive this history as enhancing their knowledge of evolution, as an irrelevant waste of time, or, in its contentious diversity, as undermining its scientific status? Answering this question calls for empirical research.