The claim that all consciousness is consciousness of something gives expression to the doctrine of intentionality, according to which all and only mental states are directed towards something: in thought, towards what is thought; in perception, to what is perceived; in desire, at what is desired. Intentionality is widely acknowledged as a central feature of our mental life. What is original with Sartre is not the endorsement of intentionality but his distinctive way of unpacking that doctrine. The distinctiveness of his approach comes out clearly in his analysis of perceptual experience. In perception the world is directly revealed to us. In looking at a tree, for instance, you do not look at the idea of a tree, or at a picture of a tree, or at some immaterial replica of a tree. You see, touch or climb on objects, not their images. You see a tree, to be sure, but you see it “just where it is: at the side of the road, in the midst of the dust, alone and writhing in the heat” (IHP 4).