Online research in philosophy

Michael Jacovides For Locke, the first step in inquiring into perception should be reflection: “What Perception is, every one will know better by reflecting on what he does himself, when he sees, hears, feels, etc. or thinks, than by any discourse of mine” (2.9.2). As a second step, I say, we may learn from reading him. Locke’s use of the term ‘perception’ is somewhat broad. At one point, he tells us that “having Ideas and Perception” are “the same thing” (2.1.9). Elsewhere, he includes the perceiving the agreement of ideas and perceiving the meaning of signs among the varieties of perception (2.21.5). What I have to say will be about perception as psychologists classify it nowadays. I will first discuss sensation in general and then elucidate some of the subtleties of Locke’s account of the visual perception of shape. I’ll close with some remarks on Locke account of time perception.

The nature of perception has long been a central question in philosophy. It is of central importance not just for the philosophy of mind, but also for epistemology, metaphysics, aesthetics, and the philosophy of science. This volume represents the best of the latest research on perception, with contributions from some of the leading philosophers in the area, including Christopher Peacocke, Brian O'Shaughnessy and Michael Tye. As well as discussing traditional problems, the essays also approach the topic in light of recent research on mental content and representation.

Often, sensory input underdetermines perception. One such example is the perception of illusory contours. In illusory contour perception, the content of the percept includes the presence of a contour that is absent from the informational content of the sensation. (By “sensation” I mean merely information-bearing events at the transducer level. I intend no further commitment such as the identification of sensations with qualia.) I call instances of perception underdetermined by sensation “underdetermined perception.” The perception of illusory contours is just one kind of underdetermined perception. The focus of this chapter is another kind of underdetermined perception: what I shall call "active perception". Active perception occurs in cases in which the percept, while underdetermined by sensation, is determined by a combination of sensation and action. The phenomenon of active perception has been used by several to argue against the positing of representations in explanations of sensory experience, either by arguing that no representations need be posited or that far fewer than previously thought need be posited. Such views include, but are not limited to those of Gibson (1966, 1986), Churchland.

The sensation-perception distinction did not appear before the seventeenth century, but since then various formulations of it have gained wide acceptance. This is not an historical accident and the article suggests an explanation for its appearance. Section 1 describes a basic assumption underlying the sensation-perception distinction, to wit, the postulation of a pure sensory stage--viz. sensation--devoid of active influence of the agent's cognitive, emotional, and evaluative frameworks. These frameworks are passive in that stage. I call this postulation the passivity assumption. Section 2 suggests three major reasons for the emergence of this assumption in the seventeenth century: the mental-physical gap, the causal theory of perception, and epistemological considerations regarding the status of the sensory given. In the last section a critical discussion is presented. The passivity assumption is found to have serious empirical and theoretical flaws.