These are the questions and considerations that Georges Canguilhem associates in 1945 with the problem of biological individuality – posed, according to him, by the concept of the cell. From his medical thesis on Quelques problèmes concernant le normal et le pathologique (1943) [Some Problems Concerning the Normal and the Pathological] until his last lectures at the Collège Philosophique in 1947, one can see an ambitious philosophical programme establish itself whose spirit can be summed up in a striking formula: ‘The problem of individuality is itself indivisible.’

The essential part of Canguilhem's œuvre is not so much the successful execution of this initial programme. It is, rather, this programme's dismantling, and then, as if by surprise, its reconstitution through the transfer of concepts. It is from this singular trajectory that it drew – and still maintains – its exceptional force of intellectual solicitation. This essay will discuss Canguilhem's work, focusing on its relation to the work of one of Canguilhem's students, Gilbert Simondon.

In the life sciences where he chose to establish himself, Canguilhem was in the same situation as Gaston Bachelard in physics in the 1920s: because of an unexpected leap of scientific progress, he was forced to ‘reeducate himself several times’.