The classical age discovered the body as object and target of power. It is easy enough to find signs of the attention then paid to the body - to the body that is manipulated, shaped, trained, which obeys, responds, becomes skilful and increases its forces. The great book of Man-the-Machine was written simultaneously on two registers: the anatomico-metaphysical register, of which Descartes wrote the first pages and which the physicians and philosophers continued, and the technico-political register, which was constituted by a whole set of regulations and by empirical and calculated methods relating to the army, the school and the hospital, for controlling or correcting the operations of the body. These two registers are quite distinct, since it was a question, on the one hand, of submission and use and, on the other, of functioning and explanation: there was a useful body and an intelligible body. And yet there are points of overlap from one to the other. La Mettrie’s L'Hommemachine is both a materialist reduction of the soul and a general theory of dressage, at the centre of which reigns the notion of ‘docility’, which joins the analysable body to the manipulable body. A body is docile that may be subjected, used, transformed and improved. The celebrated automata, on the other hand, were not only a way of illustrating an organism, they were also political puppets, small-scale models of power: Frederick II, the meticulous king of small machines, well-trained regiments and long exercises, was obsessed with them.
— Michel Foucault, Discipline and Punish