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'.

There is no reason at all to think that creatures with very different purposes and concerns would arrive at the scientific image, and no reason at all to accuse such creatures of getting the world wrong - a point that both Chuang Tzu and Nietzsche make when comparing human and animal perspectives.

Like Nietzsche, Heidegger also gave up on the prospect that schools and universities would nurture the kind of reflective openness to the way of things that, certainly by the 1940s, he identified with authentic thinking. The authentic person is not the Promethean, iron-willed figure that pops up in Nietzsche, but someone more like the Daoist sages whom Heidegger admired.

I'm very sceptical about the prospects for 'big' environmental causes - 'saving the planet', halving the world's population, ending the exploitation of animals, and so on - but a person can ask him- or herself how he or she personally may exercise compassion or humility towards animals, vegetal life and so on.

In the final analysis, all explanations of meaning, various as they are, serve to indicate how something is 'appropriate' in and to our practices, our lives in effect.

In the doctrine of the world and humankind as 'will to power and nothing else', Heidegger identified not an antidote to nihilism, but the completion of it. For what can be more destructive of truth and value than the doctrine that these are simply the impositions on the world of human exercises of power?

For many years, questions about the meaning of life were dismissed as senseless. We were told that life, not being a word or sentence or anything language-like, can't intelligibly be said to have meaning. An encouraging development in the last couple of decades is a return by philosophers to addressing - as nearly all people do at some time or another - the question of life's meaning.