M�ller, Johannes Peter 1801-58
German physiologist

Born in Koblenz, he studied at Bonn University, was appointed to the chair of physiology there in 1826, and in 1833 moved to Berlin University. He won fame for his precocious researches in embryology, and also showed early interest in the eye and vision. His later work was wide-ranging, covering electrophysiology, the glandular system, the human embryo and the nervous system. He worked on zoological classification, dealing especially with marine creatures. In 1840 he proposed the law of specific nerve energies, that is, the claim that each sensory system will respond in the same way to a stimulus whether this is mechanical, chemical, thermal or electrical. M�ller's Handbuch der Physiologie des Menschen (1833-40) was extremely influential, and he himself was probably the most significant life scientist and medical theorist in Germany in the first half of the 19th century.