Leon Trotsky
The Austro-Marxian school (Bauer, Renner, Hilferding, Max Adler, Friedrich Adler) in the past more than once was contrasted with the school of Kautsky, as veiled opportunism might be contrasted with true Marxism. This has proved to be a pure historical misunderstanding, which deceived some for a long time, some for a lesser period, but which in the end was revealed with all possible clearness. Kautsky is the founder and the most perfect representative of the Austrian forgery of Marxism. While the real teaching of Marx is the theoretical formula of action, of attack, of the development of revolutionary energy, and of the carrying of the class blow to its logical conclusion, the Austrian school was transformed into an academy of passivity and evasiveness, because of a vulgar historical and conservative school, and reduced its work to explaining and justifying, not guiding and overthrowing. It lowered itself to the position of a handmaid to the current demands of parliamentarism and opportunism, replaced dialectic by swindling sophistries, and, in the end, in spite of its great play with ritual revolutionary phraseology, became transformed into the most secure buttress of the capitalist State, together with the altar and throne that rose above it. If the latter was engulfed in the abyss, no blame for this can be laid upon the Austro-Marxian school.
What characterizes Austro-Marxism is repulsion and fear in the face of revolutionary action. The Austro-Marxist is capable of displaying a perfect gulf of profundity in the explanation of yesterday, and considerable daring in prophesying concerning to-morrow – but for to-day he never has a great thought or capacity for great action. To-day for him always disappears before the wave of little opportunist worries,