The German experimental psychologist Gustav Theodor Fechner (1801-1887) founded psychophysics and formulated Fechner's law, a landmark in the emergence of psychology as an experimental science.

Gustav Theodor Fechner was born on April 19, 1801, at Gross-Särchen, Lower Lusatia. He earned his degree in biological science in 1822 at the University of Leipzig and taught there until his death on Nov. 18, 1887. Having developed an interest in mathematics and physics, he was appointed professor of physics in 1834.

About 1839 Fechner had a breakdown, having injured his eyes while experimenting on afterimages by gazing at the sun. His response was to isolate himself from the world for 3 years. During this period there was an increase in his interest in philosophy. Fechner believed that everything is endowed with a soul; nothing is without a material basis; mind and matter are the same essence, but seen from different sides. Moreover, he believed that, by means...