Three Aspects of Perception

Abstract

Knowledge is not perception, Socrates is supposed to have proved to Theaetetus, since knowledge must be both incorrigible and (of the) real. But perception, insofar as it is incorrigible, is not of the real: it is just what seems to me now; and insofar as it is, or claims to be, of the real, it is not incorrigible: our senses, as purveyors of information, may err. So knowledge is not perception. So at least runs the traditional interpretation, which I am following here for the purpose of my argument. For the point is that even if we admit the defeat of the thesis that knowledge is perception, we still want to claim that perception is one kind of, and indeed the primordial, and fundamental, type of knowledge. For the senses are our only source of informational input from the world; without them we could know nothing. Perhaps we may drop one of Plato’s criteria (as we are taking them to be), claim that knowledge is of the real, but not incorrigible, and so admit perception to the class of cognitive activities. Perception is the most fundamental type of knowledge, on which others build, and they are all fallible: there should be, on principle, no difficulty in the case. Still, recurrent puzzles about perception have their good grounds, and I would like to try to sort out once more, very simply, some of the features that produce these puzzles.