This chapter discusses four interrelated topics. I shall first characterize Nagel's distinctive treatment of the issue of realism in more depth. As Chapter 1 established, Nagel believes that scientific understanding is capable of supplying that which Williams called an “absolute conception” of the world, namely, a conception of the world that is maximally independent of our distinctively human perspective (VN: 15; B. Williams 1978: 64–8). In the first section, “Cartesian absoluteness”, I shall describe this view in order to establish how Nagel positions himself between two kinds of critic: those who undervalue objectivity and those who overvalue it (VN: 5). This discussion is intended to set the stage for three corollaries of Nagel's realism, each of which is of considerable interest in its own right.

The first corollary that Nagel derives from his realism is a wellknown critique of what he took to be a strong tendency towards philosophical idealism in contemporary philosophy. I shall focus, in particular, on his critique of the views of Ludwig Wittgenstein and Donald Davidson. The focus of this discussion is understanding: how, in general, thought can so much as be about an objective world.

The second corollary that Nagel derives from his realism is a distinctive treatment of knowledge and scepticism. How is objective knowledge possible if we are finite and contingent creatures, products of a contingent evolutionary history, who simply find ourselves in a world not of our own making? The section “Knowledge and the shadow of skepticism” discusses the role that Nagel’s two models of objectivity described in Chapter 1, the Cartesian and the Hegelian, play in formulating his claim that there is a close connection between his view of objectivity and the irrefutability of scepticism.