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Johannes Peter Müller (July 14, 1801, Koblenz – April 28, 1858, Berlin), was a German physiologist, comparative anatomist, and ichthyologist not only known for his discoveries but also for his ability to synthesize knowledge.
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Life
In 1819 he entered Bonn University, where he became Privatdozent in 1824, extraordinary professor of physiology in 1826, and ordinary professor in 1830. In 1833 he went to the Humboldt University of Berlin, where he filled the chair of anatomy and physiology with great distinction until his death. Müller made numerous researches in various departments of physiology, and in particular he extended knowledge as to the mechanism of voice, speech and hearing, and as to the chemical and physical properties of lymph, chyle and blood.
The appearance of his Handbuch der Physiologie des Menschen between 1833 and 1840 (translated into English by Dr William Baly, and published in London in 1842) marked the beginning of a new period in the study of physiology. In it, for the first time, the results of human and comparative anatomy, as well as of chemistry and other departments of physical science, were brought to bear on the investigation of physiological problems.
The most important portion of the work was that dealing with nervous action and the mechanism of the senses. Here he stated the principle, not before recognized, that the kind of sensation following stimulation of a sensory nerve does not depend on the mode of stimulation but upon the nature of the sense-organ. Thus light, pressure, or mechanical stimulation acting on the retina and optic nerve invariably produces luminous impressions. This he termed the law of specific energies of the sense. In the later part of his life he chiefly devoted himself to comparative anatomy. Fishes and marine invertebrata were his favorite subjects. Müller numbered such distinguished scientists and physiologists as Hermann von Helmholtz 1821-1894), Emil du Bois-Reymond (1818-1896), Theodor Schwann (1810-1882), Jacob Henle (1809-1885) and Karl Ludwig (1816-1895) among his pupils.
Works
In addition to his Handbuch der Physiologie, his publications include:
- Zur vergleichenden Physiologie des Gesichtssinns (1826)
- Uber die phantastischen Gesichtserscheinungen (1826)
- Bildungsgeschichte der Genitalien (1830), in which he traced the development of the Müllerian duct
- De glandularum secerneniium structura (1830)
- Vergleichende Anatomie der Myxinoiden (1834-1843)
- Systematische Beschreibung der Plagiostomen (1841) with FGJ Henle
- System der Asteriden (1842) with FH Troschel
- Horae ichthyologicae (1845-1849) with the same.
After the death of JF Meckel (1781-1833) he edited the Archiv fur Anatomie und Physiologie.
Quote
Law of Specific Nerve Energies from: Handbuch der Physiologie des Menschen für Vorlesungen, 2nd Ed. Translated by Edwin Clarke and Charles Donald O'Malley
“. . . (T)he same cause, such as electricity, can simultaneously affect all sensory organs, since they are all sensitive to it; and yet, every sensory nerve reacts to it differently; one nerve perceives it as light, another hears its sound, another one smells it; another tastes the electricity, and another one feels it as pain and shock. One nerve perceives a luminous picture through mechanical irritation, another one hears it as buzzing, another one senses it as pain. . . He who feels compelled to consider the consequences of these facts cannot but realize that the specific sensibility of nerves for certain impressions is not enough, since all nerves are sensitive to the same cause but react to the same cause in different ways. . . (S)ensation is not the conduction of a quality or state of external bodies to consciousness, but the conduction of a quality or state of our nerves to consciousness, excited by an external cause.”