Chapter 13 of Heidegger's Nihilism book (vol.4 of Nietzsche) is entitled 'Metaphysics and Anthropomorphism'. It puts valuative thinking to one side to explore the metaphysics of modernity and Nietzsche's relation to it. This is Heidegger beginning to confront the western metaphysical tradition.

Heidegger says that modern metaphysics is characterized by the special role of the human subject and the appeal to human subjectivity. He traces this back to Descartes:

'At the beginning of modern philosophy stsands Descartes' statement Ego cogito, ego sum, "I think, therefore I am." All consciousness of things and of beings as a whole is referred back to the self-consciousness of the human subject as the unshakeable ground of all certainity. The reality of the real is defined in later times as objectivity, as something that is conceived by and for the subject as what is thrown and stands over against it. The reality of the real is representedness through and for the representing subject."

'Nietzsche's doctrine, which makes everything that is, and as it is, into the "property and product of man" merely carries out the final development of Descartes' doctrine, according to which truth is grounded on the self-certainity of the human subject.'

This interpretation is what Heidegger will defend.