Franz Clemens Honoratus Hermann Brentano (January 16, 1838 – March 17, 1917) was an influential German philosopher and psychologist whose work strongly influenced not only students Sigmund Freud (whose doctoral dissertation he helped supervise), Kazimierz Twardowski, Alexius Meinong, and Thomas Masaryk (as well as Masaryk's student, Edmund Husserl), but countless others whose work would follow and make use of his original ideas and concepts.