 On first encounter, it may seem strange that the idea of narrow content should be controversial, or even that we should need a special term for it. Most people, if they were ever to explicitly consider the issue of whether mental content is narrow or broad, would probably hold that all mental content is narrow, i.e. that all of the contents of our mental states are entirely determined by our intrinsic properties. It seems conceivable, for example, as Descartes argued in his First Meditation, that our perceptual states and beliefs could be exactly as they are even if the world were nothing like we think it is. This seems to presuppose that no difference in our environment, however radical, could make a difference to the contents of our beliefs so long as our intrinsic properties remained the same.