In collaboration with Engels, Marx also set about writing a book which is often seen as his best treatment of the concept of historical materialism, "The German Ideology". In this work, Marx broke with Ludwig Feuerbach, Bruno Bauer, Max Stirner and the rest of the Young Hegelians, while he also broke with Karl Grün and other "true socialists" whose philosophies were still based in part on "idealism". In "German Ideology", Marx and Engels finally completed their philosophy, which was based solely on materialism as the sole motor force in history. "German Ideology" is written in a humorously satirical form, but even this satirical form did not save the work from censorship. Like so many other early writings of his, "German Ideology" would not be published in Marx's lifetime and would be published only in 1932.