 Instead of thinking of direct perception of the world as built into experience, we can think of direct perception of the world as built out of experience together with the satisfaction of other conditions. This idea is usually developed through a causal theory of perception (Grice 1961): where perception of an object is analysed in terms of (i) experience of an ordinary object (conceived as something which is not sufficient for perception), and (ii) the satisfaction of a causal condition which requires that the experience be caused by the object (in a non-deviant way). This is a causal theory of direct perception on the assumption that the account doesn’t involve any perceptual intermediaries.