Between nature and music there seems to be an elective affinity: they fit together, and when they do experiences of an ineffable kind are generated.

An abiding and central concern of philosophy and religion alike is the fear that the world is alien to human beings, that nature is, in Hegel's words, 'out and out other' to 'spirit'. It's easy enough to see how 'constructivist' or 'humanist' conceptions are efforts to dispel this fear.

Nietzsche's 'perspectivalism' was expressly directed against the 'laughable juxtaposition of "man and world"'. But 'absolutist' accounts, too, typically try to demonstrate that human beings are integral components of the world these accounts articulate - that, for example, we are simply material bodies subject to the same natural processes as everything else.

Certainly each side - the 'absolutists' and the 'constructivists' or 'humanists', as I've labelled them - accuses the other of hubris, and lays claim to humility. I see hubris on both sides: a pretence that we could ascend to an objective account of the world, on the one hand, and a pretence that we have the resources to live and act without a sense of there being something to which we answerable, on the other. So both sides are 'villains'.

The dis-incumbenced stance is the one people should cultivate, we are told, once they recognize that there is no world beyond the human world. They will, indeed must, have their beliefs and values, but they will recognize that these 'lean upon' - and are answerable to - nothing other than human commitments and purposes. The only fidelity, Rorty remarked, can be to our own conventions.

The demands of the economy, and more recently those of political correctness and the diktat against ever offending anyone, are not conducive to a classroom or university seminar climate in which genuinely free and critical reflection on how to live prospers.

I was keen to dispel a familiar misunderstanding: that existentialists somehow relish the alienation of human beings from the world. This may have been Camus's attitude, but it was certainly not that of Heidegger, Sartre and Merleau-Ponty, each of whom tried to show that we can only experience the world in relation to our own projects and purposes. The world is initially one of 'equipment', said Heidegger: it is a world of 'tasks', said Sartre.