Franz Brentano

“Franz Clemens Honoratus Hermann Josef Brentano (/brɛnˈtɑːnoʊ/; German: [bʁɛnˈtaːno]; 16 January 1838 – 17 March 1917) was a German philosopher and psychologist. His 1874 Psychology from an Empirical Standpoint, considered his magnum opus, is credited with having reintroduced the medieval scholastic concept of intentionality into contemporary philosophy.

Originally a Catholic priest, Brentano withdrew from the priesthood in 1873 due to the dogmatic definition of papal infallibility in Pastor aeternus. Working subsequently as a non-denominational professor, his teaching triggered research in a wide array of fields such as linguistics, logic, mathematics and experimental psychology through the young generation of philosophers who were gathered as the School of Brentano.”

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“In 1866 he defended his habilitation thesis, Die Psychologie des Aristoteles, insbesondere seine Lehre vom Nous Poietikos (The Psychology of Aristotle, in Particular His Doctrine of the Active Intellect, published 1867), 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 in matters of Faith. A strong opponent of such dogma, he eventually gave up his priesthood and his tenure in 1873. He remained, however, deeply religious and dealt with the topic of the existence of God in lectures given at the Universities of Würzburg and Vienna.

In 1874 Brentano published his major work, Psychology from an Empirical Standpoint.”

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“Brentano is best known for his reintroduction of the concept of intentionality—a concept derived from scholastic philosophy—to contemporary philosophy in his lectures and in his work Psychologie vom empirischen Standpunkt (Psychology from an Empirical Standpoint). While often simplistically summarised as “aboutness” or the relationship between mental acts and the external world, Brentano defined it as the main characteristic of mental phenomena, by which they could be distinguished from physical phenomena. Every mental phenomenon, every psychological act has content, is directed at an object (the intentional object). Every belief, desire etc. has an object that they are about: the believed, the desired. Brentano used the expression “intentional inexistence” to indicate the status of the objects of thought in the mind. The property of being intentional, of having an intentional object, was the key feature to distinguish psychological phenomena and physical phenomena, because, as Brentano defined it, physical phenomena lacked the ability to generate original intentionality, and could only facilitate an intentional relationship in a second-hand manner, which he labeled derived intentionality.”