the political context within which its introduction, elaboration and dissemination proceeded. Indeed, each of the philosophers considered in this book repudiated the notion that the study of philosophy was a scholastic intellectual exercise devoid of political significance. Each of these philosophers regarded himself as a revolutionary, and considered philosophy to be useful precisely because it could facilitate a comprehension of the world and so accelerate efforts to change it. By the same token, each of these philosophers took philosophy seriously; each bent his mind to the daunting task of mastering the arcane and labyrinthian philosophical system of dialectical materialism. Philosophy might well be political, they believed, but this was no excuse for philosophical dilettantism.