The German philosopher and psychologist Franz Clemens Brentano (1838-1917) is best known for his work in establishing psychology as an independent science.

Franz Brentano was born on Jan. 16, 1838, at Marienberg in the Rhineland into a family of the nobility, whose lineage is traceable to the 13th century and includes many famous members, among them the authors Clemens Brentano and Bettina von Arnim. Franz studied at the gymnasium at Aschaffenburg and then at the universities of Munich, Würzburg, Berlin, and Münster (1856-1860). Raised in an extremely pious and orthodox Catholic household, Brentano early decided to enter the priesthood and was ordained in 1864.

From the first his interests were divided almost equally between theology, philosophy, and mathematics. After a period of increasing doubts about fundamental dogmas of the church, the declaration of papal infallibility in 1870 precipitated his final break with the church 3 years later. Thereafter he...