: This essay reconstructs and evaluates Aristotle’s argument in Nicomachean Ethics IX.9 that the happy person needs friends, in which Aristotle combines his well-known claim that friends are other selves with the claim that human perception is meta-perceptual: the perceiving subject perceives its own existence. After exploring some issues in the logic of perception, the essay argues that Aristotle’s argument for the necessity of friends is invalid since perception-verbs create referentially opaque contexts in which the substitution of co-referential terms fails.