Max Stirner, pseudonym of Johann Kaspar Schmidt, (1806, Bayreuth, Bavaria [Germany]-died 1856, Berlin, Prussia), German antistatist philosopher in whose writings many anarchists of the late 19th and the 20th centuries found ideological inspiration. His thought is sometimes regarded as a source of 20th-century existentialism.

After teaching in a girls' preparatory school in Berlin, Stirner made a scanty living as a translator, preparing what became a standard German version of Adam Smith's Wealth of Nations. He contributed articles to the liberal periodical Rheinische Zeitung, which was in part edited by Karl Marx. Later Marx tried to refute Stirner's ideas, ironically calling him "Sankt Max" ("Saint Max"). His most influential work is Der Einzige und sein Eigentum (1845; The Ego and His Own).
Stirner believed that there was no objective social reality independent of the individual; social classes, the state, the masses, and humanity are abstractions and therefore need not be considered seriously. He wrote of a finite, empirical ego, which he saw as the motive force of every human action. Writing chiefly for working-class readers, he taught that all persons are capable of the self-awareness that would make them "egoists," or true individuals.

Max Stirner in his book The Ego and His Own (1845) recommended, instead of social reform, a ruthless individualism that should seek satisfaction by any means and at whatever risk. A small group of other individualists.