How better to map the changes in the social body of medicine than through that most shared manifestation of disease: the epidemic?

According to Foucault, in classificatory medicine, epidemics emerged in areas in which the individual constitutions of bodies was succeptible to the natural occurrence of disease. There was no concept of direct communicability of disease, only an increased susceptibility to a natural environment in which the disease entity might be manifest:

"Not every constitution is an epidemic; but an epidemic is a finer-grained constitution, with more constant, more homogeneous phenomena...In this perceptual structure, the problem of contagion is of little importance. Transmission from one individual to another is never the essence of an epidemic...contagion is only one modality of the brute force of the epidemic." (p. 23-25)

It would then follow then epidemics weren't understood as particular diseases which tended to specifically infect large populations, rather epidemics were seen only as a coincidentally large number of people developing the same but unrelated disease states:

"There is no difference in nature or species, therefore, between an individual disease and an epidemic phenomenon; it is enough that a sporadic malady be reproduced a number of times for it to constitute an epidemic. It is a purely mathematical problem of the threshold: the sporadic disease is merely a submarginal epidemic" (p. 23).

Yet towards the end of the eighteenth century, a new means of collectively perceiving and considering the epidemic began to emerge:

"Whether contagious or not, an epidemic has a sort of historical individuality, hence the need to employ a complex method of observation when dealing with it. Being a collective phenomenon, it requires a multiple gaze; a unique process, it must be described in terms of its special, accidental, unexpected qualities. The event must be described in detail, but it must also be described in accordance with the coherence implied by multi-perception: being an imprecise form of knowledge, insecurely based while ever partial, incapable of acceding of itself to the essential or fundamental, it finds its own range only in the cross-checking of viewpoints, in repeated, corrected information, which finally circumscribes, where gazes meet the individual, unique nucleus of these collective phenomena. At the end of the eighteenth century, this form of experience was being institutionalized." (p. 25)

Thus there was the development of a new, collective, government-driven way of viewing disease that required a collective, institutionalized structure and paved over the previous "free spaces." How and why did this happen? Because in order to have a multiple, wide-surveying public gaze, the medical body needed a means of invasive public observation:

"the definition of a political status for medicine and the constitution, at state level, of a medical consciousness whose constant task would be to provide information, supervision, and constraint, all of which 'relate as much to the police as to the field of medicine proper.'" (p. 26)

New institutions were constructed and boards of regulation and boards to regulate the boards of regulation and great political conflicts ensued, but since the Gaze (and not politcal figures) is the protagonist of this book, what effect did this multiple gaze have on the concept of medicine?

Most notably, there began to emerge the idea of individual facts of medicine which existed at the overlapping areas of doctors' observations:

"What defines the act of medical knowledge in its concrete form is not, therefore, the encounter between doctor and patient, nor is it the confrontation of a body of knowledge and a perception; it is the systematic intersection of two series of information, each homogeneous but alien to each other--two series that embrace an infinite set of separate events, but whose intersection reveals, in its isolable dependence, the individual fact. A saggital figure of knowledge." (p. 30)

This emergence of the notion of individual facts was of extremely important because for the first time there were means by which one could begin to recognize a sense of consistency among experiences from different nosological systems. As such, this new ability to discern objective facts meant that "each practitioner must supplement his supervisory activity with teaching, for the best way of avoiding the propagation of disease is to spread medical knowledge...the consciousness of each individual must be alerted; every citizen must be informed of what medical knowledge is necessary and possible" (p. 31).

The logical extension of this new ability of doctors to issue certain behavioral proscriptions to society is the power of medicine to establish norms of conduct for healthful living:

"Medicine must no longer be confined to a body of techniques for curing ills and of the knowledge that they require; it will also embrace a knowledge of healthy man, that is, a study of non-sick man and a definition of the model man. In the ordering of human existence it assumes a normative posture, which authorizes it not only to distribute advice as to healthy life, but also to dictate the standards for physical and moral relations of the individual and of the society in which he lives" (p. 34).

For the sake of public health, individuals must attend to their constitutions by caring for their environment and themselves in certain ways as proscribed by the doctors. This conflation of a the curative and normative powers of medicine manifested itself in a new way of viewing medicine:

"When one spoke of the life of groups and societies, of the life of the race, or even of the 'psyhological life,' one did not think first of the internal structure of the organized being, but of the medical bipolarity of the normal and the pathological" (p. 35).

As a result, there was a profound reordering of medical perception: doctors no longer operated within the indivualized free space of medicine but now took on a public, instiutional duty to determine proper means by which normal health can be maintained. And this new authority was grounded in a new ability to distill individual facts from the intersections of collective medical observations.