Lausanne school of physical socioeconomics Auguste Walras (1801-1866) ●————||| Leon Walras(1834-1910) Leon Winiarski(1865-1915) Maffeo Pantaleoni (1857-1924) Vilfredo Pareto(1848-1923) | | ●———— ——— ● ——— ———— ● | Emanuele Sella (1879-1946) The connectivity tree of hard science based economics philosophy of the Lausanne school starting from French socioeconomist Leon Walrus to the two cultures synergy of Italian economist Maffeo Pantaleoni, to that of Emanuele Sella who studied under Pantaleoni.
In schools, Lausanne school of physical socioeconomics, a two cultures synergy, refers the 1858 to 1946 physical science based economics and sociology models of French political economist Auguste Walras, his son socioeconomist Leon Walras, French-born Italian engineer Vilfredo Pareto, Polish social mechanics economist Leon Winiarski, Italian economist Maffeo Pantaleoni, and Italian lawyer and political economist Emanuele Sella, centered at the University of Lausanne, Switzerland.

History
In 1858, French political economist Auguste Walras, during a walk with his 24-year-old son socioeconomist Leon Walras, told the young Walras that: [1]

“To create a scientific theory of economics one would need to use differential calculus to derive a ‘science of economic forces, analogous to the science of astronomical forces’.”

This seed idea catapulted Leon to go on to formulate a general equilibrium theory of economics, which soon attracted the reading attention of French-born Italian engineer Vilfredo Pareto, who eventually in 1893 would succeed Leon Walrus as chair of political economy at the University of Lausanne, and friend-follower Polish social mechanics economist Leon Winiarski, who would go on to teach a course on Pure Political Economics and Social Mechanics at the University of Geneva, Switzerland, from 1896 to 1903, or thereabouts. Italian economist Maffeo Pantaleoni, Pareto's closest intellectual two cultures synergy associate, and his student Emanuele Sella were also connected in this Lausanne school circle. Economics historians Benedicte Berthe and Michel Renault give the following Winiarski connection view of the Lausanne school: [3]

Leon Winiarski, a friend of Leon Walras and member of the Lausanne school, made the principle of least effort the ‘basis of social science’ (Winiarski, 1903).”

In 1870, when Walras became professor of political economics at Lausanne, to about 1903, the year about which Winiarski was still publishing applied concepts, is thereabouts the launching point of the Lausanne school. The following 2005 quote by Mainzer Klaus summarizes retrospect gist of the Lausanne school: [2]

“The Lausanne school explicitly used mathematical terms of thermodynamics, like equilibrium, to describe economic balance.”

All three of them conceived of people as economic molecules or human molecules; the latter two explicitly used thermodynamic concepts in formulating economic and sociological theory.

Leon Walras
In his early development, Leon Walras was influenced by the views of John Locke, John Mill, and from Rene Descartes, arguing the supposition that utility, defined as the "intensity of the last want satisfied", is measurable in economics, akin to mass being measurable in mechanics as the "number of molecules" or "quantity of matter", such that utility might be rendered measureable "as is done with temperature". In 1901, he wrote to French mathematician Henri Poincare (IQ=195): [4]

“You have made me very happy by explaining to me with the authoritativeness that you command that I was justified in representing the satisfaction of individuals by functions.”

Pareto
The contributions of Vilfredo Pareto are rather extensive; as are the extensions of his works into various economics schools (e.g. Harvard Pareto circle). His complete works total some 20 books or booklets, more than 600 articles in journals, magazines, and newspapers, and over 100 published book reviews, introductions, prefaces, and or interviews, on subjects including: physics, mathematics, statistics, public policy, and sociology (Ѻ)
 In 1990, the Walras-Pareto Center for Interdisciplinary studies (see: interdisciplinarity) was established at the University of Lausanne; a noted member of which is Swiss economics historian Francois Allison, a scholar on Leon Winiarski, Nikolai Bukharin and the history of Russian economics (Karl Marx, Vladimir Lenin, etc.). [5]

Winiarski
It is difficult, at this point, to say who, in retrospect, is the biggest chief genius of the Lausanne school: Vilfredo Pareto or Leon Winiarski, being that a complete English-translated set of their respect works, is not yet available? Winiarski, however, seems to have gone a step above Pareto in his thermodynamics usage, particularly his use of the reversible cycle to explain social energy.

In 1898, Winiarski, in his Essay on Social Mechanics, chapter ten “The Social Energy”, states the following rather impressive logic:

“The imperative nature of morality, law, etc., does nothing special and mysterious it very well in between the action of the laws of mechanics and just means that some transformation of energy, which correspond to irreversibilities. But like all irreversible cycles tend to their evolution towards a state of full reversibility ensures that only a maximum, the binding nature and imperative of social institutions weakens over the course of time. [19]

Note 19:
With the conditions of complete reversibility in the second principle:

$\int \frac{dQ}{T} = 0$

is in fact the starting point for another reason. If experience leads us to establishing the equation:

[or $\oint \frac{dQ}{T} = 0 \,$meaning closed line or path integral?]

for a closed cycle and reversible, it should be a function of independent variables do not sear the differential an exact differential. In other words:

$\frac{dQ}{T} = dS \,$

or S is a function of x and y, such that dS, will be an exact differential on a plot of x and y. It is this function that S that Clausius has called the name of entropy, a function which presents some analogy with that of the energy (U). Indeed, the like energy, entropy is a property of the body completely determined by the current values of variables and it follows that pet always be translated by a formula which expresses the function of these independent variables. As for energy incurs, its value should not depend of the path followed by a body to reach its current state, in case this is not a full cycle of operations. One can always express entropy by the equation:

$\frac{dQ}{T} = dS \,$

but only, of course, for a reversible cycle.”

This discussion, as we see, is well-ahead of its time, hardly anything like this, with it intermixing of discussion on morality, weakening of social institutions, and reversibility, described in terms of circle integrals, can be found at present.

Sella

Other
In 1995, Italian political economist Claudia Rotondi did her 1995 PhD on Pantaleoni, Pareto, and Sella.

Quotes
The following are related quotes:

Walras was an agrarian socialist and wanted to nationalize land, but he talked of humans as ‘economic molecules’ and gave concepts like scarcity scientific definitions analogous to heat in physics.”
— Hazel Henderson (1981) [1]

References
1. Ingrao, B. and Israel, G. (1990). The Invisible Hand, (pgs. 87-88). Cambridge, MA: MIT Press.
2. Mainzer, Klaus. (2005). Symmetry and Complexity: the Spirit and Beauty of Nonlinear Science (Lausanne school, pg. 19). World Scientific.
3. (a) Winiarski, Leon. (1903). “Le principe de moindre effort comme base de la science sociale”, Publisher/Journal.
(b) Berthe, Benedicte and Renault, Michel. (2001). “Economic Analysis of Human Effort in Organizations: an Historical and Critical Perspective”, in: Evolution and Path Dependence in Economic Ideas: Past and Present (editors: Pierre Garrouste and Stavros Ioannides) (§9, Lausanne school, Winiarski, pg. 184). Edward Elgar Publishing.
4. Walker, Donald A. (2005). Walrasian Economics. Cambridge University Press.
5. (a) Walras Pareto Center for Interdisciplinary Studies (FrenchEnglish) – University of Lausanne.
(b) Walras Pareto Center (about) (French → English) – University of Lausanne.
(c) Francois Allisson – Francois.Allisson.co.