devoid of such talent. When governing or nongoverning elites attempt to close themselves to the influx of newer and more capable elements from the underlying population, when the circulation of elites is impeded, social equilibrium is upset and the social order will decay. Pareto argued that if the governing elite does not "find ways to assimilate the exceptional individuals who come to the front in the subject classes," an imbalance is created in the body politic and the body social until this condition is rectified, either through a new opening of channels of mobility or through violent overthrow of an old ineffectual governing elite by a new one that is capable of governing. Governing elite Pareto introduced a social taxonomy that included six classes, Class I through Class VI. Class I corresponds to the adventurous "foxes" in Machiavelli, and Class II to the conservative "lions," particularly in the governing elite. Not only are intelligence and aptitudes unequally distributed among the members of society, but the residues as well. Under ordinary circumstances, the "conservative" residues of Class II preponderate in the masses and thus make them submissive. The governing elite, however, if it is to be effective, must consist of a strong mixture of both Class I and Class II elements. The ideal governing class contains a judicious mixture of lions and foxes, of men capable of decisive and forceful action and of others who are imaginative, innovative, and unscrupulous. When imperfections in the circulation of governing elites prevent the attainment of such judicious mixtures among the governing, regimes either degenerate into hidebound and ossified bureaucracies incapable of renewal and adaptation, or into weak regimes of squabbling lawyers and rhetoricians incapable of decisive and forceful action. When this happens, the governed will succeed in overthrowing their rulers and new elites will institute a more effective regime. Speculators What applies to political regimes applies to the economic realm as well. In this field, "speculators" are akin to the foxes and "rentiers" to the lions. Speculators and rentiers do not only have different interests but they reflect different temperaments and different residues. Neither is very good at using force, but they both otherwise fall roughly into the same dichotomous classes that explain political fluctuations. In the speculator group Class I residues predominate, in the rentier group, Class II residues. . . . The two groups perform functions of differing utility in society. The