 This way of motivating the conceptual constraint has been explicitly put forward by several authors who argue forcibly for the second thesis (see, for example, Peacocke 1983, McDowell 1994a, Brewer 1999, and Noë 1999). Theorists of nonconceptual content, in contrast, accept the first constraint without the second. They hold that specifications of content must respect the way a thinker, perceiver or speaker apprehends the world and because of this they cannot be circumscribed by the concepts possessed by the thinker, perceiver or speaker. Theorists of nonconceptual content postulate the existence of ways of representing the world (and hence the existence of a type of content) that outstrip the concepts possessed by the thinker.