Possibly the biggest philosophical question on my mind is this: why should we do anything at all? Or, why should we do one thing and not another? What is it to have a reason for action, a reason to do anything? It’s difficult to have a coherent ethics without answering this question in some respect; but in some ways it’s even more difficult to answer the question itself.

There are, I think, two basic classes of answer to this question, which analytic philosophers classify as internalism and externalism with respect to ethical motivation. On an internalist view, to have a reason to do something is to have a motivation, perhaps even a desire, to do it. If you don’t at some level want to do something, or at least feel or believe that you should do it, then you shouldn’t do it. On an externalist view, by contrast, reasons are independent of us. There are things we just should do, period, whether or not we have any desire or other motivation to do them.

Each position faces wrenching difficulties. The externalist view is always subject to the laughing, scathing criticism of a Nietzsche. If you can’t tell me why I would want to do something, then bollocks to your “should.” I’ll do what I want instead. External reasons don’t feel like real reasons; Bernard Williams, indeed, has argued that they only really become reasons for action if we acquire motivations to do them. Yet the internalist view seems to collapse into relativism and conservatism. If our existing motivations are the only source of reasons for action, then how can those motivations ever be criticized? On what grounds can you tell Pol Pot he’s doing the wrong thing by killing his citizenry? You run, effectively, into the problems with classical relativism, which show up in a variety of ways, such as the political problems of postmodernism, or the problems of contradiction for spiritual growth.

Some way of reconciling internalism and externalism, without the problems of each, seems necessary. But what way?

What makes the question of ethical internalism and externalism still more intriguing is that it seems to parallel a very similar theoretical question about truth. Could there be a truth we can’t know? Say, a kind of knowledge only achievable by gods and not humans? If so, on what grounds can we say that something really is a truth, if we can’t know it? If not, do we not collapse back into the problems of relativism, where everything is subjective, since knowledge is reducible to our own minds?