Individualism and Marr's computational theory of vision

A great deal of philosophical work has addressed the question of whether Marr's computational theory of early vision is individualistic. Purge and Davies have argued that, according to Marr's theory, visual states are individuated non-individualistically. Segal has denied that Marr's theory has these non-individualistic implications. More recently, Shapiro has argued that the entire debate has been misguided. I argue that Shapiro is mistaken in a fairly deep way, attention to which allows us to raise and clarify several important issues involved in discussions of individualism. Contrary to Purge and Davies, and by a route rather different from Segal's, I defend the claim that Marr's theory offers no reason to think that visual states are individuated non-individualistically.