Epistemology - behind this word lay more than just a philosophical sub-discipline questioning knowledge in the intellectual Paris of the 1960s and 1970s. Epistemology became the dominant academic discourse of the time among structuralists, Marxists, deconstructionists, and many other critical thinkers who practiced radical thought between the university, the café, and the street. As a magic formula of philosophy, it represented an intellectual stance that purported to encapsulate the world of thought. Epistemology posed a challenge: philosophy could only derive its themes and questions from engagement with contemporary scientific thought. Therefore, Georges Canguilhem, Michel Foucault, Louis Althusser, and others reflected on modern natural sciences.