N ico O rlandi dominated the philosophy of mind Indeed, with some notable exceptions (Bermudez 2000; Jackson 1977; O’Shaughnessy 2003), most contemporary philosophers of perception reject sense-data theory Two alternative theories of perception emerged: adverbialism and representationalism or intentionalism The latter continues to be influential today (Armstrong 1961; Burge 2005; 2009; Dretske 1969; Harman 1990; Lycan 1996; Peacocke 1983; Searle 1983; Tye 1992) The former enjoyed popularity in the mid-20th century (Chisholm 1957; Ducasse 1942; Sellars 1975) We should look at each in turn 1.2 Representationalism or intentionalism Representationalists point out that the ontological commitments of sense-data theory are peculiar when we recognize that perceiving is a psychological state and, like other psychological states, it can have objects that not exist When I think of a unicorn, I am in a psychological state that is about an entity that does not exist It is hard to see why the mere fact that I can think of a unicorn would imply both that the unicorn exists, and that its perceived properties are present in the world Similarly, it is not clear why we would want to suppose that perceiving something means that the object perceived exists, and that we should discover properties corresponding to the perceived properties in the natural environment The fact that psychological states are about objects (that may not exist) is labeled their ‘intentionality’ The fact that such states tell us something about the objects they are about is called their intentional ‘content’ Sense-data theory has been charged with ignoring the intentionality of perception, for instance by G.E.M Anscombe (Anscombe 1965; Searle 1983) Anscombe argues against both sense-data theory and direct realist positions by pointing out that what she calls ‘sensation’ – and what I have been calling ‘perception’ – is similar to other mental attitudes in relating us to intentional objects.6 Prior to Anscombe, the emphasis on intentionality is present in authors such as Chisholm, Husserl, Merleau-Ponty and Brentano, who reintroduced the very concept of intentionality from Scholastic philosophy (Brentano 1874; Chisholm 1957; Husserl 1900/01; 1913; Merleau-Ponty 1945; Montague this volume) Husserl distinguishes the psychological act of perceiving – the noesis – from its content – the noema, which directs itself to an object A perceptual act with a given content can occur in the absence of its object while still aiming at it Representationalists about perception tend to also be representationalists about qualia (Anscombe 1965; Byrne 2001; Dretske 1995; Harman 1990; Lycan 1987; Shoemaker 1994; Tye 1994) There are different versions of representationalism about qualia, but the general idea is that qualia are represented properties of represented objects Some express this view by saying that qualia are ‘representational properties’ They are properties of what is represented in perceptual experience When I am hallucinating a white wall, for example, I am representing a wall as having the property of being white The wall does not need to be present in my 108