Between "Usual" and "Ideal

Aristotle's slippery use of physis

“Nature” (physis) is a theme in Aristotle’s Physics, Ethics, and Politics. Yet, according to Julia Annas, he “never systematically investigates nature as an ethical or political concept” (Review of Metaphysics 49.4 [1996] 731). That leaves him vulnerable, Annas says, to “reactionary” uses of the category of nature; Aristotle has been used to justify slavery, subordination of women, and other forms of inequality.

Aristotle sometimes says physis is “the cause of what is the same way always or for the most part, and chance of the opposite.” Something is natural if “starting from some internal principle, it develops continuously ‘always something going towards the same thing, if nothing interferes.’” In this sense, nature is “the usual” (732). At other times, though, nature is the ideal, and things that don’t measure up to the ideal are “unnatural.”

Aristotle sometimes slips back and forth between these definitions within a single passage. At the beginning of the Politics, he talks about the naturalness of slavery and the polis, and also distinguishes between natural and unnatural uses of money. Slavery is natural because “every known society contained slavery” (732); that is, the natural is “the usual.” When talking about money, he says nearly the opposite: “the only form of natural money-making is one which is extremely rare,” which indicates that the natural is the ideal, “something not actually found in the world as it is” (733). These two definitions move in opposing moral and political directions: If nature is an ideal, it can serve as a critical norm by which to measure the actual arrangements of society; if nature is “what is usual,” then nature cannot critique but simply justifies whatever happens to be the case.

Aristotle’s arguments in Book 7 of the Politics also turn on the ambiguity of physis.