In this paper, I explore the role that metaphor plays in the development of new scientific models. My goal is to illustrate metaphor’s fecundity in this regard, the way in which it extends our understanding in surprisingly diverse ways. As Mary Hesse put this point, “it is precisely in its extension that the fruitfulness of the model may lie” (1980, 114).
The particular focus of my paper is on the history of what John Haugeland called mind design: the use of mechanical models to reverse-engineer how minds work (1997, 1). My history focuses on two such models: the clockwork model and the computer model. In each case, I show how a metaphorical understanding of the model led to conceptual innovation in two distinct ways. First, it provided an interpretive frame that guided new research by offering an abstract, hypothesized structure to be later filled in by empirical research (Camp 2020). Second, it provided a concrete exemplar to contrast with human minds (Daston 1994). For instance, while on the one hand Descartes invoked the clockwork model to explain how color vision works (Adams 2015), he also invoked it as a vivid illustration of how human reasoning does not work (Riskin 2016).
It is this second source of conceptual innovation that is the real core of the paper; it reveals what I call the dialectic of mind design. This dialectic is especially evident in our tendency to redefine what it is to be human in response to new technological developments. For instance, it is evident when we take something that was previously assumed to be paradigmatic of mental acuity, such as the ability to play chess, and redefine it as something merely mechanical (Ensmenger 2012). But it is equally well evident when we take something that was previously taken to be mechanical—such as color vision—and redefine it as paradigmatically mental (Chalmers 1997; cf. Adams and Browning 2020). The concept of mindedness is, in this sense, a constantly moving goalpost that is perennially being redefined in response to new technological developments.