Abstract

We attempt to clarify the nature of philosophic assertions about perception by considering how one can argue effectively against such assertions. Reasons are given, with illustrative assertions from Aristotle and Berkeley, why one cannot argue effectively against such either (1) by arguing for contrary assertions in competing theories or (2) by appealing to scientific observation. Effective arguments against such accounts include (1) those which demonstrate inconsistency within the account, (2) those which disclose an unintelligibility within the account, and (3) those which show the account is inadequate in scope. These are illustrated respectively by arguments (i) against Phenomenalism, (ii) against Aristotle's account of the identity in act of sensing faculty and sensed object, and (iii) against Berkeley's account of observation through instruments.