“Brentano was a philosopher and psychologist who taught at the Universities of Würzburg and Vienna. He made significant contributions to almost every branch of philosophy, notably psychology and philosophy of mind, ontology, ethics and the philosophy of language. He also published several books on the history of philosophy, especially Aristotle, and contented that philosophy proceeds in cycles of advance and decline. He is best known for reintroducing the scholastic concept of intentionality into philosophy and proclaiming it as the characteristic mark of the mental. His teachings, especially those on what he called descriptive psychology, influenced the phenomenological movement in the twentieth century, but because of his concern for precise statement and his sensitivity to the dangers of the undisciplined use of philosophical language, his work also bears affinities to analytic philosophy.”
From: Roderick M. Chisholm and Peter Simons, “Brentano, Franz Clemens” in: Routledge Encyclopedia of Philosophy, Edited by Edward Craig, London: Routledge 1998.