ABSTRACT
Whatever their other differences, Husserl and Heidegger defended the autonomy of philosophy with respect to the social or natural sciences. Such a defense of philosophy, however, has been a minority viewpoint throughout most of the twentieth century when compared to epistemological naturalism. Karl Mannheim adopts the term "psychologism" to refer to the thought of those who wish to restrict their study of cognition to either psychological or neurophysiological topics. Georg Lukacs's philosophical defense of Marxism exercised an especially powerful, if somewhat underground, influence on a whole generation of philosophers in the continental tradition, coinciding, it would seem, with the quick rise and fall of existentialism and phenomenology. Easily the most influential opposition to both Mannheim and Lukacs was ironically another naturalistic project. During the 1960s and 1970s, the intellectual movement called structuralism, like existentialism before it, gained as much popular cultural notoriety as it did theoretical and philosophical influence.
