Thought and reasoning are correct or incorrect in virtue of something independent of the thinker’s beliefs, and even independent of the community of thinkers to which he belongs. We take ourselves to form true beliefs about the world around us, about timeless domains of logic and mathematics, and about the right thing to do. We don’t take these capacities to be infallible, but we think they are often reliable in an objective sense, and that they can give us knowledge. The natural internal stance of human life assumes that there is a real world, that many questions, both factual and practical, have correct answers, and that there are norms of thought which, if we follow them, will tend to lead us toward the correct answers to those questions. It assumes that to follow those norms is to respond correctly to values or reasons that we apprehend. Mathematics, science, and ethics are built on such norms.
— Thomas Nagel, from Why the Materialist Neo-Darwinian Conception of Nature is Almost Certainly Wrong, p. 71