Franz Clemens Honoratus Hermann Brentano (January 16, 1838 – March 17, 1917) was an influential German philosopher and psychologist whose influence was felt by other such luminaries as Sigmund Freud, Edmund Husserl, Kazimierz Twardowski and Alexius Meinong, who followed and adapted his views.
Brentano was born at Marienberg am Rhein, near Boppard. He studied philosophy at the universities of Munich, Würzburg, Berlin (with Adolf Trendelenburg) and Münster. He had a special interest in Aristotle and scholastic philosophy. He wrote his dissertation in Tübingen On the manifold sense of Being in Aristotle. Subsequently he began to study theology and entered the seminary in Munich and then Würzburg and entered the Jesuit order. He was ordained a Catholic priest on August 6, 1864. In 1865/66 he wrote and defended his habilitation essay and thesis and began to lecture at the University of Würzburg. His students in this period included, among others, Carl Stumpf and Anton Marty. Between 1870 and 1873 Brentano was heavily involved in the debate on papal infallibility. A strong opponent of such dogma, he eventually gave up his priesthood and his tenure in 1873 and in 1879 left the church altogether.
In 1874 Brentano published his major work: "Psychology from an Empirical Standpoint" and from 1874 to 1895 taught at the University of Vienna. Among his students were Edmund Husserl, Alexius Meinong, Christian von Ehrenfels, Rudolf Steiner, T.G. Masaryk, Sigmund Freud, Kazimierz Twardowski and many others (see School of Brentano for more details). While he began his career as a full ordinary professor, he was forced to give up both his Austrian citizenship and his professorship in 1880 in order to marry. He was permitted to return to the university only as a Privatdozent. After his retirement he moved to Florence in Italy, transferring to Zürich at the outbreak of the First World War, where he died in 1917.