Philosophy since Kant has been, well, neo-Kantian. Indeed, neo-Kantianism in philosophy arguably predates Kant by a considerable time. Locke, Berkeley, and Hume were all neo-Kantians. Kant was a neo-Kantian. Hegel was a neo-Kantian, as was Marx (at least the Marx of the first and second Internationals). Nietzsche, that most professedly anti-Kantian of thinkers, was a neo-Kantian. The linguistic turn in philosophy is essentially a linguistic form of neo-Kantianism. Mainstream twentieth-century philosophy of science has been about as neo-Kantian as you can get. Structuralism is neo-Kantian. And anybody, but anybody, who writes about literary theory is neo-Kantian to their intellectual core. As you might have already gleaned, I am using the expression ‘neo-Kantian’ in a somewhat broad sense. Indeed, the way I am using the expression makes it difficult to imagine anyone who is not neo-Kantian. Neo-Kantianism is the view that there are activities of the mind whose function is to structure the world. At least some aspects of the world that is presented to us, therefore, are mind-dependent in that they depend for their existence or nature on the structuring activities of the mind. The significance of recent strands of thought that have been labelled externalist, or antiindividualist is that they effectively invert this picture of the relation of mind to world. What is essential to externalism, or, as I shall call it here, environmentalism, in all its forms, is the idea that the contents of the mind are, in some sense at least, worldly: they are environmentally constituted. This does not, of course, provide a refutation of neo-Kantianism, but it does, in effect, turn neo-Kantianism on its head.