Karl Bühler was born in Meckesheim near Heidelberg. Like Ach, he first studied medicine, worked as a ship's doctor, and then turned to philosophy, which he studied with Carl Stumpf in Berlin and Benno Erdmann in Bonn, among others.
From 1906-1909 he was an assistant to Külpe in Würzburg and followed him to Bonn and later to Munich. His habilitation thesis (1907/1908) "Tatsachen und Probleme zu einer Psychologie der Denkvorgänge ("Facts and Problems for a Psychology of Thought Processes") led to a conflict with Wilhelm Wundt, which brought the Würzburg School into the public interest of science.
The photo shows Karl Bühler in the period between 1900 and 1905. From 1906 he worked at the Würzburg Institute for Psychology as an assistant to Oswald Külpe.
Photo: Archiv der Universität Wien, 131.147 Bühler, Charlotte und Karl; Teil-Nachlass ("Exil-Nachlass"), Karton 1541