" Guérin's leftist, class-based critique of Jacobinism thus had three related implications for contemporary debates about political tactics and strategy. First, it implied a rejection of "class collaboration" and therefore of any type of alliance with the bourgeois Left (Popular Frontism). Second, it implied that the revolutionary movement should be uncompromising, that it should push for more radical social change and not stop halfway (which, as Saint Just famously remarked, was to dig one's own grave), rejecting the Stalinist emphasis on the unavoidability of separate historical "stages" in the long-term revolutionary process. Third, it implied a rejection both of the Leninist model of a centralised, hierarchical party dominating the labour movement and of the "substitutism" (substitution of the party for the proletariat) which had come to characterize the Bolshevik dictatorship. "

― Daniel Guérin , For a Libertarian Communism