An Introduction to Metaphysics is the key text for understanding the development of Bergson's thought from his early treatises on duration (Time and Free Will and Matter and Memory) to the extension of this concept towards a general cosmology (Creative Evolution) and an ethico-political ontology (The Two Sources of Religion and Morality). It achieves this by simultaneously deepening and broadening the scope of duration within both a new theory of metaphysics and a new methodology. In fact, the ultimate consequence of this proliferation of what Bergson also called 'real time' is a totally novel understanding of metaphysics and philosophical method as such, one that shows how they are actually facets of the one and the same process. Against the naysayers of anti-metaphysics (Wittgenstein, Heidegger, Derrida), Bergson shows how metaphysics can be re-established as a material thinking that avoids the aporia of logic and language by returning to its function as that which ruins every essence and keeps thinking in duration, a non-symbolic method of 'differentiations and integrations', that puts thought into 'reverse', and that thereby becomes part of 'the very life of things'. In a new critical edition of this crucial work, the original, authorised translation by T.E. Hulme has been restored and supplemented with new translations of Bergson's later amendments to the text, a guide to further reading, and a new introduction by Bergson scholar, John Mullarkey.