For me, the existentialists are important critics of 'absolutist' claims, and Heidegger and Merleau-Ponty are, at least in their later writings, also exponents of a doctrine of mystery: Being or the 'well-spring' of everything is, for Heidegger, ineffable, just as what Merleau-Ponty called 'Flesh' is for him.

What impressed me about Plato and Sartre was their conviction that we should live our lives in the light of big truths about reality and human existence.

In all great civilizations, garden discourses have belonged to larger discourses about beauty, the good life, the relation of humankind to nature, and so on.

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.

The Overman will himself be a nihilist in the (good) sense of rejecting any metaphysical or religious grounding for truth and value, but instead of curling up in despair, or simply going along with the crowd like the 'passive' nihilist, he will recognize himself as the sole source of truths and values to live by.

The focus of environmental ethics should indeed be on the virtues and how these inform our relationship to natural environments.

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.