In 1842 he became editor of the Rheinische Zeitung, but his demands for radical reforms led to its suppression in 1843. He then went to Paris, where he began his lifelong association with Friedrich Engels. At this time Marx became a socialist. He devoured the works of Adam Smith, David Ricardo, the comte de Saint-Simon, and many others. Antagonized by the individualistic radicalism of Pierre Joseph Proudhon, Marx attacked him in The Poverty of Philosophy (1847, tr. 1910), an early attempt to systematize his own thought. In this period also he wrote, with Engels, The German Ideology (tr. 1933), which provided an exposition of his dialectical materialism. Breaking with the tradition of justifying social reform by appeal to natural rights, he invoked "inevitable" laws of history to predict the eventual triumph of the working class.