How people make gardens is bound to reflect a way of experiencing the natural world, while at the same time this experience of nature is bound to reflect a culture - ways of painting nature, for example, or representing nature in literature, or of course making gardens.

It would be through individual effort, inspired perhaps by reading Nietzsche's books, that the Overman might emerge, not through social or educational engineering.

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.

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.

Like Nietzsche's own writings on education, most of mine were relatively youthful ones. Both were inspired by a critical animus against prevailing trends in education: in Nietzsche's case, the production either of 'useless', dry-as-dust scholars or people 'useful' for the needs of an expanding industrial economy; in my case, a similar subjection of education to economic imperatives, but also to ideological obsessions, notably with promoting 'equality'.

Gardening is an excellent example of a practice to which, as Alasdair MacIntyre puts it, certain virtues are 'internal'. Good gardening requires a certain goodness on the part of the gardener: care, humility, patience, and respect, for example.

Does the unmistakeable intent of Versailles to proclaim dominion over nature destroy its aesthetic appeal, as Schopenhauer thought? Does the greenness of the lawn lose its allure when we learn how much water, sorely needed elsewhere, it uses? And historical shifts in garden taste - from formal, 'French' gardens to 'Capability' Brown's landscapes, for instance, or from the elaborate gardens of imperial Kyoto to Zen 'dry' gardens - register important changes in philosophical or religious attitudes.