Foucault associates nineteenth-century treatments for madness with punishment and the regulation of behavior. They also split up an earlier whole. Nineteenth century treatments relate to different diseases, which have a specific location, rather than to the patient's entire body and soul.
The idea of madness as moral evil is still a central theme. The relationship between madness and morality is characteristic of nineteenth century psychology. Psychology for Foucault is more about morality than science. Only when morality and madness are completely linked is psychology possible. Although classical physicians may talk to or reason with their patients, and appear to treat their minds, this is not a truly psychological approach. Reasoning is not enough; only moral judgment and an attempt to use guilt as a treatment represents a truly psychological approach.
After making this key distinction, Foucault analyzes specific methods of treatment. Most cures center on the concept of delirium. They attempt to alter or reconfigure the discourse of delirium. They therefore work with language and idea rather than with the body. In its classical form, delirium essentially means a movement away from the correct path of reason. These treatments try to direct it back onto the right track.
The various cures differ in their attitude to the discourse of delirium. "Awakening" moves the patient back towards reason by reasoning with him. Foucault's reference to Descartes is important here; he refers to a another aspect of the Cogito this time. Foucault uses the idea that Descartes confirms his own existence by reasoning. The physician does not literally make the madman recite Descartes' arguments, but he does attempt to lead him towards reason and an awareness of sanity by means of reason.
Theatrical representation is very different because it involves continuing delirium. By agreeing with the patient and even acting out insane fantasies, the physician hopes to reestablish rationality. Playing along with a madman who believes himself to be Louis XIV, then slowly directing him away from this belief is a good example of this approach. It is a concerted attempt to manipulate madness back into reason from within.
The return to the immediate is the most complex of all these techniques. It draws upon earlier ideas of the animal quality of madness, and of "anti-nature". The madman can be like a beast, and is opposed to the rational order of nature. But by confronting him with the order of nature, the physician can make him rational again. "Natural obligations" like the need for food and sleep, and the rhythm of the seasons can restrain madness through their own inner logic. Ultimately, this kind of treatment supposes that the doctor can control and shape nature as well as his patient.