The Argument from Illusion and the Uniqueness Assumption

Abstract

I argue that the mainstream formulation of the argument from illusion is invalid, and the Uniqueness Assumption which makes the argument valid is suspicious because the intuition of the assumption stems from common sense which is challenged by the argument from illusion. I show that even if sense data were admitted as objects in illusions, the subject can still perceive something real; she can perceive a composite. This means that the sense-datum account of illusion need not apply to perception.