For the “passages as relevant then as now” file, Rudolf Rocker argues against the view that material factors alone determine the course of history:

[N]ever before were economic conditions riper for a complete transformation of capitalistic society. The whole capitalist economic system has gotten out of control. The crisis, which formerly was only a periodic phenomenon of the capitalistic world, has for years become the normal condition of social life. Crisis in industry, crisis in agriculture, crisis in commerce, crisis in finance! All have unite to prove the inadequacy of the capitalistic system are condemned for life to miserable beggary in the midst of a world which is being ruined by its surplus. But the spirit is lacking– the socialistic spirit that strives for a fundamental reconstruction of social life and is not content with petty patchwork, which merely prolongs the crisis but can never heal its causes. Never before has it been so clearly proved that economic conditions alone cannot change the social structure, unless there are present in men the spiritual and intellectual prerequisites to give wings to their desires and unite their scattered forces for communal work. – Rudolf Rocker, Nationalism and Culture (1937), p. 32-33.