An ideal type is an analytical construct that serves the investigator as a measuring rod to ascertain similarities as well as deviations in concrete cases. It provides the basic method for comparative study. "An ideal type is formed by the one-sided accentuation of one or more points of view and by the synthesis of a great many diffuse, discrete, more or less present and occasionally absent concrete individual phenomena, which are arranged according to those one-sidedly emphasized viewpoints into a unified anlaytical construct." An ideal type is not meant to refer to moral ideals. There can be an ideal type of a brothel or of a chapel. Nor did Weber mean to refer to statistical averages. Average Protestants in a given region or at a give time may be quite different from ideal typical Protestants. The ideal type involves an accentuation of typical courses of conduct. Many of Weber's ideal types refer to collectivities rather than to the social actions of individuals, but social relationships within collectivities are always built upon the probability that component actors will engage in expected social actions. An ideal type never corresponds to concrete reality but always moves at least one step away from it. It is constructed out of certain elements of reality and forms a logically precise and coherent whole, which can never be found as such in that reality. There has never been a full empirical embodiment of the Protestant Ethic, of the "charismatic leader," or of the "exemplary prophet."

Ideal types enable one to construct hypotheses linking them with the conditions that brought the phenomenon or event into prominence, or with consequences that follow from its emergence. If we wish to study the religious roots of modern capitalism, it may be advisable to construct an ideal type of Protestant, based on the distinct features of sectarians as these emerged during the Reformation. We shall then be in a position to determine empirically whether the concrete conduct of Protestants in, say, seventeenth-century England did in fact approximate the type and in what specific aspects it failed to do so. This type will further allow us to distinguish between the conduct of men who adhered to Catholic or Protestant religious bodies. We can then proceed to correlations and causal imputations as to the connections between the emergence of Protestantism and that of modern capitalism--both being conceived in ideal typical terms. As Julien Freund puts it, "Being unreal, the ideal type has the merit of offering us a conceptual device with which we can measure real development and clarify the most important elements of empirical reality."

Weber's three kinds of ideal types are distinguished by their levels of abstraction. First are the ideal types rooted in historical particularities, such as the "western city," "the Protestant Ethic," or "modern capitalism," which refer to phenomena that appear only in specific historical periods and in particular cultural areas. A second kind involves abstract elements of social reality--such concepts as "bureaucracy" or "feudalism"--that may be found in a variety of historical and cultural contexts. Finally, there is a third kind of ideal type, which Raymond Aron calls "rationalizing reconstructions of a particular kind of behavior." According to Weber, all propositions in economic theory, for example, fall into this category. They all refer to the ways in which men would behave were they actuated by purely economic motives, were they purely economic men.

From Coser, 1977:223-224.