There are at least two reasons that might be cited for undertaking the historical and comparative investigation of revolution. The first is the desire to make a revolution, the second is the desire to prevent it. Perhaps nearly everybody is susceptible to the one reason or the other, but there is yet a third reason that gives the study of revolution a compelling interest and significance, even though its appeal is doubtless much more limited. This is that the understanding of revolution is an indispensable condition for the fuller knowledge and understanding of society. Depending on how we define it, revolution may be common or uncommon, frequent or rare. But in the case of societies, nations, and communities that have experienced revolution, we cannot claim to understand them adequately without understanding their revolutions. In a deep and therefore a nontautological sense, it is true that every people gets the revolution it deserves and equally true that it gets only the revolutions of which it is capable.

Well over a century ago, Alexis de Tocqueville, one of the best minds that ever devoted itself to the problem of revolution, stated the rationale for the comparative history of revolutions. “Whoever studies and looks only at France,” he declared, “will never understand anything, I venture to say, of the French revolution.” Tocqueville's precept, however, has been honored far more in the breach than in the observance. Despite the general recognition of the need for systematic comparative treatment of revolution, work toward this end has remained the exception and relatively undeveloped.