The reaction against the conception of Marxism as a positive science was affected by intellectual trends but also by political circumstances. As Stuart Hughes has observed,¹ the revolt against positivism had already developed strongly during the decade of the 1890s, and its influence soon extended to Marxist thought. Croce, even during the brief period of his interest in Marxism, had conceived it as a method of historical interpretation, profoundly connected with Hegel's philosophy, and not as a general social science. Sorel, after initially taking the side of Bernstein in the "revisionist" controversy,² later presented Marxism as the theory of revolutionary syndicalism,³ but there was always a certain consistency in his view. What he praised in Bernstein's work was not only the effort to observe and describe the real world, but also its activist orientation, its invitation to socialists to play a "truly effective role" in the world, and above all its emphasis on the moral element in socialism. For Sorel was always critical of the idea of historical inevitability, and argued that socialism is primarily a moral doctrine, bringing to the world "a new manner of judging all human acts' or, to use Nietzsche's expression, "a transvaluation of all values"; it "confronts the bourgeois world as an irreconcilable adversary, threatening it with a moral catastrophe much more than with a material catastrophe".⁴