Richard Avenarius, the German positivist philosopher, was born in Paris. He studied at the University of Leipzig, where he became a Privatdozent in philosophy in 1876. The following year he was appointed professor of philosophy at Zürich, where he taught until his death. His most influential work was the two-volume Kritik der reinen Erfahrung (1888–1890), which won him such followers as Joseph Petzoldt and such opponents as Vladimir Il'ich Lenin.

Avenarius was the founder of empiriocriticism, an epistemological theory according to which the task of philosophy is to develop a "natural concept of the world" based on "pure experience." To obtain such a coherent, consistent view of the world requires a positivistic restriction to that which is directly given by pure perception, together with the elimination of all metaphysical ingredients which man, through introjection, imports into experience in the act of knowing.

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