Foucault on history

I would like to distinguish between the “history of ideas” and the “history of thought.” Most of the time a historian of ideas tries to determine when a specific concept appears, and this moment is often identified by the appearance of a new word. But what I am attempting to do as a historian of thought is something different. I am trying to analyze the way institutions, practices, habits, and behavior become a problem for people who behave in Specific sorts of ways, who have certain types of habits, who engage in certain kinds of practices, and who put to work specific kinds of institutions. The history of ideas involves the analysis of a notion from its birth, through its development, and in the setting of other ideas which constitute its context. The history of thought is the analysis of the way an unproblematic field of experience, or a set of practices, which were accepted without question, which were familiar and “silent,” out of discussion, becomes a problem, raises discussion and debate, incites new reactions, and induces a crisis in the previously silent behavior, habits, practices, and institutions. The history of thought, understood in this way, is the history of the way people begin to take care of something, of the way they become anxious about this or that—for example, about madness, about crime, about sex, about themselves, or about truth. Michel Foucault, Fearless Speech, Semiotext(e), 2001, p. 74.