Most philosophers agree that beliefs and perceptions represent the world to us and that a particular belief or perception is sometimes distinct from another particular belief or perception because what they represent is different; for example, one thing that distinguishes the belief that snow is white from the belief that grass is green is that the former represents snow while the latter represents grass. However, most philosophers of mind hold that a particular belief or perception is sometimes distinct from another (...) particular belief or perception because of how they represent. Indeed, though few philosophers explicitly recognize a distinction between what something represents and how it represents, the view that there is more to belief and perception than what they represent is about as close to philosophical orthodoxy as anything is. In this dissertation, I give a substantive account the relevant notion of representation and the distinction between what something represents and how it represents. I also bring out this hidden orthodoxy and argue that it is mistaken. Contrary to the orthodoxy, I defend the view that belief and perception present a single class of mental phenomena marked by their representational nature and that any mental difference between any two members of the class must be a difference in what they represent. (shrink)