In thermodynamics schools, Helmholtz school is a crossover school of physics and physiology that refers to the group of German medical students Ernst Brücke, Emil Du Bois-Reymond, and Carl Ludwig under the leadership of Hermann Helmholtz, at the University of Berlin, and their view that living organism operate according to physical-chemical principles, rather than vitalism or other special biological theories. [1]

In 1845, the group formed the Berlin Physical Society, in efforts to promote the view that organisms are governed solely by physiochemical forces, rather than by those connected to vitalism. The term "Helmholtz school" was used as early as 1944 by Austrian psychologist Siegfried Bernfeld in his article “Freud’s Earliest Theories and the School of Helmholtz”. [2]

Central in this group was Herman Helmholtz and his universal theory of the conservation of force (later incorporated into the first law of thermodynamics). The idea of the conservation of force was passed along in the teachings of Brücke to Austrian psychologist Sigmund Freud, one of Brücke’s students at the medical school at Vienna, during the years 1873-78, who later used this logic to revolutionize psychology with his theories of conservations of forces, such as in repressions or cathexis, in the subconscious.

Müller’s laboratory
In 1826, German physiologist Johannes Müller scripted his law of specific energies of the sense, with focus on nerve energies, arguing that the act of sensation depends on some special quality of energy carried by the transmission nerves, e.g. the optic nerve. [3] In this description was a premise of vitalism. In circa 1833, his Handbook of Human Physiology came out, which integrated, to an extent, aspects of human and comparative anatomy, chemistry, and physics.


Emil Du Bois-Reymond (1818-1896)	Ernst Brücke (1819-1892)
The two associates of the famous 1842 "Reymond-Brucke oath" that the insides of organisms are governed solely by physical-chemical means.

During the years 1838-42, Emil Du Bois-Reymond, Ernst Brücke, and Hermann Helmholtz were worked together in Müller’s physiology laboratory. Though Helmholtz gave his name to the school, as he later became the most prestigious (one of the founders of chemical thermodynamics), it was actually started by Du Bois-Reymond and Brücke, who in 1842 pledged their famous oath (Reymond-Brucke oath): [4]

“[We pledge] to put in power this truth: no other forces than the common physical chemical ones are active within the organism. In those cases which cannot at the time be explained by these forces one has either to find a specific way or form of their action by means of physical mathematical method, or to assume new forces equal in dignity to the chemical physical forces inherent in matter, reducible to the force of attraction and repulsion.”

It is difficult to discern why 1842 was such a decisive year, but it could have something to do with the publication of Justus Liebig's Animal Chemistry (1842) which utilized the vitalist doctrine, mixed with Antoine Lavoisier's combustion theory of animal heat, on the premise that by 1845, Helmholtz had scrutinized Liebig’s vitalism-soaked theory that animal heat theory could be accounted for by the combustion of food, by pointing out that there was no rigorous theoretical justification for such a claim. [6]

The trio, Reymond, Brucke, and Helmholtz, not note, were soon joined by Helmholtz and a young physician named Carl Ludwig, who had previously completed his medical degree in 1839 and the University of Marburg, forming the Berlin Physical Society (Berliner Physikalische Gesellschaft) in 1845. The members of the society, according to one view, “were young students of Johannes Müller – physicists and physiologists banded together to destroy, once and for all, vitalism, the fundamental belief of their admired master.” [4]

On July 23, 1847, at a meeting of the Berlin group, when it was still more a club than a formal scientific association, Helmholtz read a paper on the principle of conservation of energy – with the modest purpose of giving a sound foundation to the new physiology. This was said to have “made an enormous impression” on everyone at the school of Helmholtz. [3] Through the later influence of Brücke on Freud, the energy view of psychoanalysis can clearly be found in works of Freud such as his “Instincts and Their Vicissitudes” in his chapter seven of The Interpretation of Dreams, where psychological issues are described in terms of cathectic energies and their transformations or vicissitudes.

Ludwig, like his associates, he rejected the assumption that the phenomena of living animals depend on special biological laws and vital forces different from those which operate in the domain of inorganic nature; and he sought to explain them by reference to the same laws as are applicable in the case of physical and chemical phenomena. This point of view was expressed in Ludwig's celebrated Text-book of Human Physiology (1852-1856), but it is as evident in his earliest paper (1842) on the process of urinary secretion as in all his subsequent work.

To the group, and especially Brücke, any hint of vitalism was verboten (forbidden); biological systems were to be thought of as mere extensions of inanimate physical systems. [5] In some mentions, Austrian physician Josef Breuer is said to have been associated with the Helmholtz school.

See also
● Berlin school of thermodynamics

References
1. (a) Grof, Stanislav. (1985). Beyond the Brain: Birth, Death, and Transcendence in Psychotherapy (pg. 143). SUNY Press.
(b) Yalom, Irvin D. and Leszcz, Molyn. (2005). The Theory of Practice and Group Psychotherapy (pg. 99). Basic Books.
(c) Brome, Vincent. (1968). Freud and His Early Circle (pgs. 2-3). Morrow.
2. Bernfeld, Siegfried. (1944). “Freud’s Earliest Theories and the School of Helmholtz”, Psychoanalytic Quarterly, Vol. 13, (pgs. 314-62, esp. pg 348).
3. Law of specific nerve energies - Wikipedia
4. Murray, Henry A. and White, Robert W. (2006). The Study of Lives: Essays on Personality in Honor of Henry A. Murray (pg. 372-75). Aldine Transaction.
5. Geissler, Hans-Georg, Link, Stephen W., and Townsend, James T. (1991). Cognition, Information Processing, and Psychophysics (pg. 24). Lawrence Erlbaum Associates.
6. Mirowski, Philip. (1989). More Heat than Light: Economics as Social Physics, Physics as Nature’s Economics (triangle, pg. 130). Cambridge University Press.