Though often employed as a catchall term in contemporary usage, including some philosophers' usage, ideology has a clearly identifiable historical origin and since its invention has borne some clear though disparate meanings (as well as, to be sure, some unclear ones) in several traditions of thought, most notably in the Marxian tradition.

It was Antoine Destutt de Tracy who, toward the end of the eighteenth century, conceived the notion of developing a science of ideas that would trace them back to their supposed material elements. The group around him became known as the Idéologues and at first found favor with Napoleon Bonaparte, whose coup ending the period of the French Revolution and its immediate aftermath they at first applauded. But they soon became his vehement critics (concerning, for example, his policy-driven revival of religion), and Napoleon returned the compliment by denouncing them for, among other things, allegedly...