It is a commonplace among certain recent philosophers that there is no such thing as the essence of anything. Nietzsche, for example, asserts that things have no essence of their own, because they are nothing but ceaselessly changing ways of acting on, and reacting to, other things. Wittgenstein, famously, rejects the idea that there is an essence to language and thought – at least if we mean by that some a priori logical structure underlying our everyday utterances. Finally, Richard Rorty urges that we ‘abandon … the notion of “essence” altogether’, along with ‘the notion that man's essence is to be a knower of essences’.

It would be wrong to maintain that these writers understand the concept of essence in precisely the same way, or that they are all working towards the same philosophical goal. Nevertheless, they do share one aim in common: to undermine the idea that there is some deeper reality or identity underlying and grounding what we encounter in the world, what we say and what we do. That is to say, they may all be described as anti-foundationalist thinkers – thinkers who want us to attend to the specific processes and practices of nature and humanity without understanding them to be the product of some fundamental essence or ‘absolute’.