The Human Model: Polymorphicity and Scientific Method in Aristotle’s _Parts of Animals_

[penultimate draft; prepared for publication in Aristotle’s Parts of Animals: A Critical Guide, ed. Sophia Connell – please cite final version] Parts of Animals II.10 makes a new beginning in Aristotle’s study of animals. In it, Aristotle proposes to “now speak as if we are once more at an origin, beginning first with those things that are primary” (655b28-9). This is the start of his account of the non-uniform parts of blooded animals: parts such as eyes, noses, mouths, etc., as opposed to uniform parts like blood and flesh. PA II.10 proposes a new strategy for studying these parts: “one ought to speak about the human kind first” (656a10). Beginning “first” with the “primary” things thus amounts to beginning with humans (655b28-9). Why does Aristotle think this strategy is appropriate for his project? One answer is that it reflects a fundamental anthropocentrism. Lloyd, for instance, has raised the possibility that the basic assumptions that guide Aristotle’s biology may to some extent reflect the anthropocentrism of his culture, where the relation of humans to animals was “a preoccupation of popular beliefs”. In this paper, I develop an interpretation that both builds on and challenges this suggestion. I do so by investigating how Aristotle thinks this strategy works in theory and in practice: his justifications for adopting it and its interaction with his scientific commitments. I argue that Aristotle adopts it in part because he thinks that humans are such that his scientific concepts apply to them in a particularly clear way. (This too is a form of anthropocentrism: one that might be resisted by arguing that humans are not the best illustrations of these concepts—that Aristotle ought to look elsewhere for models with the features he desires.) More specifically, Aristotle holds that starting with humans helps establish the causal explanations of the parts of other animals, particularly when they are recalcitrant. What makes humans suitable for this role is a special teleological relation between their parts and the ends they serve: in humans, he supposes, this connection is particularly tight (in a way I explain below). Consequently, Aristotle thinks he can use humans to illuminate which sorts of features tend to be for the sake of which ends, and then extend the results of this inquiry to the parts of the other animals