Abstract
Recent work in visual perception shows that its phenomenal and cognitive aspects cannot be distinguished sharply. A preferable treatment of visual perception is to describe perceptual strategies, which represent the various ways in which perceivers may focus interest, and which are treated in this paper by two examples. Perceptual strategies suggest that both Sense Data theories, on the one hand, and treatments of perception such as Hanson's, on the other, are over-simplified. This work further suggests that the traditional distinction between primary and secondary qualities should be replaced by an epistemological distinction between visual and physical qualities. Such a distinction clarifies epistemological investigations of perception and shows the relevance of experimental investigations of visual perception to epistemological problems.