The appearance in nineteenth-century psychiatry, jurisprudence, and literature of a whole series of discourses on the species and subspecies of homos… - Michel Foucault

There has been an inversion in the hierarchy of the two principles of antiquity, “Take care of yourself” and “Know yourself.” In Greco-Roman culture, knowledge of oneself appeared as the consequence of the care of the self. In the modern world, knowledge of oneself constitutes the fundamental principle.

But let there be no misunderstanding: it is not that a real man, the object of knowledge, philosophical reflection or technological intervention, has been substituted for the soul, the illusion of theologians. The man described for us, whom we are invited to free, is already in himself the effect of a subjection more profound than himself. A 'soul' inhabits him and brings him to existence, which is itself a factor in the mastery that power exercises over the body. The soul is the effect and instrument of a political anatomy; the soul is the prison of the body.

I try to carry out the most precise and discriminative analyses I can in order to show in what ways things change, are transformed, are displaced. When I study the mechanisms of power, I try to study their specificity... I admit neither the notion of a master nor the universality of his law. On the contrary, I set out to grasp the mechanisms of the effective exercise of power; and I do this because those who are inserted in these relations of power, who are implicated therein, may, through their actions, their resistance, and their rebellion, escape them, transform them—in short, no longer submit to them. And if I do not say what ought to be done, it is not because I believe there is nothing to be done. Quite on the contrary, I think there are a thousand things to be done, to be invented, to be forged, by those who, recognizing the relations of power in which they are implicated, have decided to resist or escape them. From this point of view, my entire research rests upon the postulate of an absolute optimism. I do not undertake my analyses to say: look how things are, you are all trapped. I do not say such things except insofar as I consider this to permit some transformation of things. Everything I do, I do in order that it may be of use.