Ekrem Çetinkaya

This article explains Aristotle’s view of conflicting appearances of the same objects in perception. Examining his responses to the Protagoreans who take all such appearances as true, the article argues that Aristotle treats this epistemological position as fundamentally metaphysical. He distinguishes two versions of Protagoreanism, each connected to a distinct metaphysical thesis: a realist thesis urging simultaneous ascription of contrary perception-independent qualities to objects, and an anti-realist thesis making perceptible qualities’ existence dependent on perception. Against both positions, Aristotle develops a restrictive realist response that preserves the perception-independent existence of qualities while denying that all appearing qualities actually belong to objects—thereby indicating the previously underappreciated scope of his realism. Rather than revising our conception of the world’s uniform structure, Aristotle suggests that we should treat conflicting appearances as perceptual deceptions arising from deviations in perceivers’ conditions such as illness, distance, or weakness.

Aristotle grants perceptible qualities the power to generate sense perception in animals. But it is unclear whether, for him, these qualities can produce any effect other than perception. In this paper I address this issue through a novel approach. To show that they can produce non-perceptual effects, I explore contexts in his extant works where qualities appear to do causal work in nature without leading to perception in animals. This inquiry aims to demonstrate that Aristotle’s realism about qualities survives a potential threat posed by views that dispute the qualities’ causal efficacy outside perception.