 The political revolutions of the Enlightenment, especially the French and the American, were informed and guided to a significant extent by prior political philosophy in the period. Though Thomas Hobbes, in his Leviathan (1651), defends the absolute power of the political sovereign, and is to that extent opposed to the revolutionaries and reformers in England, this work is a founding work of Enlightenment political theory. Hobbes’ work originates the modern social contract theory, which incorporates Enlightenment conceptions of the relation of the individual to the state. According to the general social contract model, political authority is grounded in an agreement (often understood as ideal, rather than real) among individuals, each of whom aims in this agreement to advance his rational self-interest by establishing a common political authority over all. Thus, according to the general contract model (though this is more clear in later contract theorists such as Locke and Rousseau than in Hobbes himself), political authority is grounded not in conquest, natural or divinely instituted hierarchy, or in obscure myths and traditions, but rather in the rational consent of the governed. In initiating this model, Hobbes takes a naturalistic, scientific approach to the question of how political society ought to be organized (against the background of a clear-eyed, unsentimental conception of human nature), and thus decisively influences the Enlightenment process of secularization and rationalization in political and social philosophy.