
A depiction of the 1930s and early 1940s Harvard Pareto circle according to American sociologist Barbara Heyl, centered around the 1890s to 1910s work of Vilfredo Pareto, intermixed or rather upgraded with the "systems" based chemical thermodynamics equilibrium model work of Willard Gibbs, via the lead of American physical chemistry trained physiologist Lawrence Henderson. [1]

A depiction of the 1930s and early 1940s Harvard Pareto circle according to American sociologist Barbara Heyl, centered around the 1890s to 1910s work of Vilfredo Pareto, intermixed or rather upgraded with the "systems" based chemical thermodynamics equilibrium model work of Willard Gibbs, via the lead of American physical chemistry trained physiologist Lawrence Henderson. [1]

In schools, Harvard Pareto circle, aka “Pareto circle” at Harvard, Pareto clique, Hendersonians, or “Pareto cult”, as some liberals and Marxists pejoratively referred to it—not to be confused with any of the original Pareto schools or circles one might derive from original Lausanne school—refers to efforts of American physical chemist and physiologist Lawrence Henderson who, from 1932 up through 1942, worked to bring the dense physicochemical rational mechanics based economics and social theories of Italian engineer Vilfredo Pareto, integrated with newer chemical equilibrium views of American engineer Willard Gibbs, to bear on students and professors at Harvard University, humanities applied.

The "circle", as it was dubbed, included the notable individuals: George Homans, characterized by Leon Warshay as being "mechanistic", Charles Curtis, a good friend of Henderson who gave some assistance in running the two year course on Pareto, Joseph Schumpeter, Talcott Parsons, Bernard DeVoto, Crane Brinton, and Elton Mayo, who each, at Harvard University, attended the two-year (1932-34) seminar or course entitled “Pareto and the Methods of Scientific Investigation” run by Henderson on Italian engineer Vilfredo Pareto's unified large-scale modelling of socio-political phenomena and history, via the “society as a system of mutually interacting particles”, making equilibrium adjustments. [1]

The combination of the start of WWII, the reaction end (death) of Henderson (1942), and a switch to Karl Marx based sociology and economics focus, admixtured with Max Weber, brought about a demise of the circle.

Wheeler → Henderson | Pareto | 1926
American psychologist Burrhus Skinner gives a rather detailed account of the circa 1926 origin or beginnings of the Harvard Pareto circle as follows: [23]

“Pareto’s influence had reached Harvard through a strange accident: Professor L.J. Henderson, who may be remembered longer for his Fitness of the Environment than for his pioneering work in the chemistry of blood, had ulcers. In the middle or late twenties he was recovering from an attack in a hospital in his beloved Paris [see: genius hiatus effect], when his friend William Wheeler, the entomologist, brought him a copy of Pareto’s Traite. Henderson read it with complete absorption during the rest of his stay in the hospital and on the voyage back to America, and he returned to Cambridge a dedicated convert. He was then director of the Fatigue Laboratory at Harvard Business School, which was already involved in projects very close to sociology and social anthropology, and he organized a series of seminars on Pareto.

One of the friends with whom Henderson talked about Pareto was Bernard DeVoto, who was then teaching at Harvard. DeVoto had a young tutee of the class of 32 named George Homans. He told George that he should read Pareto, and George did—‘at least the first volume’ at that time, as he later reported. DeVoto [then] introduced George to Henderson, and because George had read Pareto, Henderson asked him to help in his seminar. And that was how George spent his first year out of Harvard—as an assistant to L.J. Henderson without pay.”

(add discussion)

Etymology
In 1966, American equilibrium historian Cynthia Russett was referring to people who came under the influence of Lawrence Henderson’s expositions on equilibrium—specifically a mixture of the hard version (Willard Gibbs based) and soft version (Walter Cannon based) of equilibrium, as she classified things—as adherents of ‘Hendersonianism’. While she doesn’t use the term “circle” or “school”, in her chapter entitled ‘Epogony’, signifying follower or disciple, she gives the following group of Hendersonians: [14]

“The roster of men who came under Lawrence Henderson’s influence, whether as student, colleague, or friend, is long and distinguished. Among the Harvard faculty during the 1930s Henderson’s views measurably affected Wallace Donham, Elton Mayo, Fritz Roethlisberger of the Harvard School of Business Administration; the historian Crane Brinton; and the historian and essayist Bernard DeVoto. The poet Conrad Aiken, the businessman Chester I. Barnard, author of the classic organizational study The Functions of Executive, and the lawyer and legal historian Charles Curtis, Jr. also acknowledged and intellectual debt to Henderson. George Homans and Talcott Parsons, both sociologists, and Eliot D. Chapple and Conrad Arensberg, anthropologists, absorbed some basic Hendersonian tenets.”

In 1968, independent, it seems, of Russett, the term Harvard "Pareto circle" was introduced in by American sociologist Barbara Heyl, in the title of her article “The Harvard ‘Pareto Circle’”, which focuses on four specific individuals of the Henderson circle of influence: Henderson, naturally, followed by George Homans, Talcott Parsons, and Crane Brinton. The following is Heyl's diagram of the "Parato circle" timeline association diagram, of her four main players of interest, in respect to who attended the Pareto seminar (1932-34), the Society of Fellows meetings, and or the Saturday Club, each different groups at Harvard, wherein Pareto began to be discussed: [1]

Soon thereafter, Heyl's article soon became "one widely cited article" (Joel Isaac, 2008), the term "Pareto circle" stuck, and Heyl's article currently (2014) is cited about 100 times in Google scholar.

Harvard Paretians (Hendersonians)
1.	Lawrence Henderson	Physical chemist
2.	Talcott Parsons	Sociologist
3.	Joseph Schumpeter	Economist
4.	Charles Curtis	Legal historian
5.	George Homans	Sociologist
6.	Bernard DeVoto	Historian
7.	Wallace Donham	Business scholar
8.	Crane Brinton	Historian
9.	Pitirim Sorokin	Sociologist
10.	Bernard Barber	Sociologist
11.	Elton Mayo	Industrial psychologist
12.	Fritz Roethlisberger	Business scholar
13.	Conrad Aiken	Poet
14.	Chester I. Barnard	Businessman
15.	Eliot D. Chapple	Anthropologist
16.	Conrad Arensberg	Anthropologist
17.	Robert Merton	Sociologist
18.	Thomas Kuhn	Paradigm scholar
19.	C. Wright Mills	Sociologist
20.	Henry Murray	Psychologist
21.	Clyde Kluckhohn	Social anthropologist
22.	William Wheeler	Entomologist
23	Edwin Wilson	Polymath
24.	Paul Samuelson	Economist
25.	James Miller	Psychologist

Overview
In 2000, American sociologist Steve Fuller, in his chapter subsection “The Harvard Strategy for Resisting a New Deal for Science”, gives a rather cogent nuts and bolts summary the Pareto circle: [5]

“Harvard’s Pareto Circle, which was convened from 1932 to 1942, spawned a theory of revolution that stressed, true to the original Latin, a ‘turning back’, a restoration of natural order. The circle’s convener was the practicing biochemist, certified physician, and amateur sociologist Lawrence Henderson. Among the circle’s members were the future luminaries of sociology as Talcott Parsons, George Homans, and Robert Merton, as well as intellectual historian Crane Brinton, and occasionally Joseph Schumpeter, who had taken up a professorship at Harvard in 1932. The official charge of Henderson’s group was to discuss the ideas of the Italian founder of modern sociology, the political economist Vilfredo Pareto, and independently wealthy scholar of encyclopedia ambitions and Machiavellian dispositions.”

Fuller goes on to comment how Benito Mussolini regarded Pareto as such a formative influence on his own fascist ideology that he made Pareto a peer in Italy’s House of Lords; that people in the middle third of the twentieth century often referred to Pareto as the “Marx of the master class” and one of the founding fathers of sociology, along with Karl Marx, Emile Durkheim, and Max Weber; that Pareto, supposedly, was inspired by Machiavelli’s distinction between two types of human instincts, one oriented toward tradition (lions) and one toward innovation (foxes), and that this is from where he gets his circulation of elites theory, in part, from; and that Harvard chemist (1916) turned Harvard president (1933) James Conant—whose uncle-in-law was Henderson—and his recruitment of Thomas Kuhn resulted in Kuhn becoming a vicarious Pareto theorist in influence; among other footnoted details.

In 2008, English American history scholar Joel Isaac, in his “The Harvard Pareto Circle Revisited” seminar paper, refers to Heyl's article as a "one widely cited article", and summarizes the subtleties of the Pareto connection epicenter at Harvard quite well, as follows: [2]

“The Harvard ‘Pareto circle’ occupies a peculiar position in the history of modern social thought. On the one hand, the band of Harvard University students and faculty members that embraced Pareto’s Trattato di Sociologia Generale for a relatively brief moment in the 1930s is frequently identified as the source of several, usually conservative, traditions of inquiry in the American social sciences. The origins of structural-functional sociology, organization theory, industrial psychology, and the history and sociology of science have been traced to the Pareto vogue in Depression-era Cambridge.

On the other hand, however, the historical footprint of the circle is by all accounts slight. Even those who credit the Harvard Paretians with considerable feats of ideological innovation point only to desultory examples of their activities in the precincts of Harvard Yard: a seminar here, a letter there. As a consequence, much of the scholarly literature on the Pareto circle concerns itself with tracing lines of influence through a relatively narrow set of published texts. The clinching move of such studies is usually the demonstration that this or that seminal figure—Talcott Parsons, say, or Thomas Kuhn—has deployed a particular concept from the Paretian armoury: “system,” “equilibrium,” “the circulation of elites,” and so on.”

Isaac, after stating that, in his view, the Pareto circle is much larger than Heyl describes, states that the reason for writing his symposium paper is to overturn Fuller's earlier "political reading" of Pareto, as he calls it. Isaac also lists the following as having attended the symposium: Thomas North Whitehead, Hans Zinsser, Clyde Kluckhohn, W. Lloyd Warner, Henry Murray, Robert K. Merton, William Foote Whyte, and Kingsley Davis.

Assimilation
Many of the Pareto workshop attendees would later go onto employ and profess what they had learned in followup publications. Industrial psychologist Elton Mayo, in his 1933 The Human Problems of an Industrial Civilization, for example, stated the following: [20]

“The physiologists have found that work can continue to be performed only in a ‘steady state’, only for so long as an inner equilibrium is maintained between a large number of mutually dependent variables.”

Anthropologist Eliot Chapple, in association with Carleton Côôn, in their 1942 Principles of Anthropology, state the following: [21]

“Every institution, political or otherwise, must necessarily work out an equilibrium, if it is to survive.”

Moreover: [21]

“Human history is a record of continual change in the adjustments of people and of institutions, of continuous shiftings of states of equilibrium.”

Sociologist Talcott Parsons seems to have been the one to carry forward the torch of equilibrium the most. In his 1951 The Social System, he supposedly outlined the view that of equilibrium as the tendency of systems to maintain certain stable patterns of activity and interaction among their component parts, a stability that enables systems to maintain their boundaries relative to their environment. Parson’s defined equilibrium as follows: [22]

“Equilibria is the empirically observed pattern constancies of a boundary-maintaining system.”

Moreover: [22]

“The denial of [equilibrium’s] legitimacy in the conceptual armory of social science is at the least, in my perhaps not very humble opinion, symptomatic of the denial that social science itself is legitimate, or realistically possible.”

Here, interestingly, we see Parsons devoting definitional focus to the boundary problem. In this period, Parsons played an active role in the Macy conferences (1946-1953) on systems theory, and began to read the works of Norbert Wiener and Ross Ashby.

The assimilation of the equilibrium models into the mind of sociologist George Homans is an interesting case study. Adrift after graduating from Harvard in the depression year of 1932, Homans accepted an invitation of Henderson to sit in on his first series of seminars on Pareto. Toward the end of the conference, in 1934, lawyer Charles Curtis, a friend of the Homans’ family, also an attendee of the seminar, suggested that they collaborate on an exposition of Pareto’s sociology. The result was the 1934 An Introduction to Pareto. At this point, it seems, Homans gave what seems to be summaries of what he had just absorbed, e.g. “most societies at most times” have a tendency to be in equilibrium. Sixteen years later, at the time of his 1950 The Human Group, Homans had grown more, and he had begun to rethink his earlier formulations of equilibrium. He now wrote: “some social groups under some circumstances” are in equilibrium. Moreover:

“Not every state of a social system is a state of equilibrium, nor does every social system ‘seek’ equilibrium.”

In 1961, at the time of publication of his Social Behavior: its Elementary Forms, his views diverted even more: (Ѻ)

“Equilibrium is not a state toward which all creation moves.”

Here, it seems, Homans is grasping with vestiges of coupling theory? Or possibly, on a remote chance, he had begun to read up on nonequilibrium state theory and or nonequilibrium thermodynamics? We also, to note, see possible religiously coded phrasing, namely "creation", being employed. Interesting turn of mind, nevertheless.

	vs.		→
Karl Marx (1818-1883)		Vilfredo Pareto (1848-1923)		Max Weber (1864-1920)
In the 1930s, "Marxism" or equal workers in a one level workers state theory was in vogue at Harvard. The alternative, emerging in 1932, was "Paretism" or unequal workers (work based on individual level of agitation) in spinning social pyramid theory. [18] The two theories frequently collided in debate at Harvard in the period 1932 to about 1942, after which Paretism fell off in place of a growing attachment to the theories of Max Weber.

Marx vs Pareto | WWII → Weber
In the early 20th century, Vilfredo Pareto was often referred to as the “Marx of the bourgeoisie”, “Marx of the master class”, or “Karl Marx of the bourgeoisie or of fascism” (Henderson, 1935), and in this sense, Pareto was employed as an alternative to Marxism or Karl Marx dominated sociology. The following diagram shows the general difference between Paretism (left) and Marxism (right), the social structure view advanced by Pareto being one of a social pyramid spinning top, filled with people conceptualized as molecules, in which elites circulate based on their respective level of agitation, the social structure advocated by Karl Marx, being one of a equal level social structure, filled with people likewise conceptualized as molecules, albeit ones conceptualized as all being equal in wealth, work output, and ideology: [17]

In the 1930s, according to Barbara Heyl, the Marxist framework was particularly in vogue; but Pareto’s writings posited a comparable albeit alternative grand historical theory to the Marxist approach. American sociologist George Homans wrote the following about this: [16]

“As a Republican Bostonian who had not rejected his comparatively wealthy family, I felt during the thirties that I was under personal attack, above all from the Marxists. I was ready to believe Pareto because he provided me with defense.”

American historian Crane Brinton, likewise, wrote the following: [16]

“At Harvard in the thirties there was certainly, led by Henderson, what the then Communists or fellow-travelling or even just mild American style liberals in the University used to call ‘the Pareto cult.’ The favorite smear phrase for Pareto was ‘Karl Marx of the bourgeoisie.’ The Pareto cult was never one that influenced a majority of the faculty, but it had fairly wide repercussions.”

Heyl summarizes that the Marxists and Paretans frequently confronted one another at Harvard in the thirties, and that many tended to embrace Pareto’s ideas, if not in reaction to the prevailing Marxist notions on campus, as a useful defense in debate against them. The zeal of Henderson-Pareto model, however, for some reason, lost fuel during the course of WWII (1939-45), after which a switch to focus on a Max Weber (in place of Pareto) based sociology occurred as the alternative to Marxism. [15]

American sociologist Talcott Parsons (1968) gave his opinion that the reason for the fall off of Pareto-interest, after WWII, was scientific limitation: [18]

“Most of the neglect of Pareto stems from the scientific limitations of subsequent generations of sociologist rather than from his irrelevance to their interests.”

This seems cogent. With the passing (reaction end) of Henderson in 1942, there was no one qualified—a physical chemistry and or chemical thermodynamics background needed at a minimum to translate Pareto's ideas into the language of reaction equilibrium physical chemistry and modern Gibbsian thermodynamics—and capable—Henderson spent the years 1926 to 1932 absorbing the corpus of Pareto’s works (~10 volumes)—enough to lead the way further; hence, into the mid 1940s the wake of the Henderson-driven wave began to reside.

Mechanistic	vs.	Anti-Mechanistic
Lawrence Henderson (1878-1942)		Pitirim Sorokin (1889-1968)
Russian-born American sociologist Pitirim Sorokin, with his anti-social mechanism position, was the sole arguer, in opposition to American physical chemist Lawrence Henderson, and his Pareto-based physicochemical mechanics model of society.

Henderson | Sorokin
American economist Roy Weintraub, in his 1991 Stabilizing Dynamics: Constructing Economic Knowledge, has documented a certain number of background letters illuminating connections between Edwin Wilson, Paul Samuelson, Pitirim Sorokin, and Joseph Schumpeter, all Pareto circle members, with a very interesting discussion on how Wilson taught or was attempting to teaching some type of physical chemistry and or thermodynamics based economics course. [6] Firstly, quoting from George Homans 1984 autobiography, we find the following: [7]

“The seminar met for a couple of hours late in the afternoon for the better part of the academic year in, I think the junior Common Room of the Winthrop House. Henderson worked slowly through the Traite, providing his exegesis of selected passages. After each of these he would ask for questions. If there were none, he would go on. Except from Sorokin, I do not remember there was much argument. Toward the end of the first year of the seminar Charlie Curtis approached me and suggested that we collaborate in writing an introduction to Pareto’s sociology for American readers.”

The mention of Pitirim Sorokin being the sole arguer in this 1932-33 seminar would certainly have been something to see. A mere skim of Sorokin’s 1928 opening chapter “The Mechanistic School” (see: mechanistic school), of his Contemporary Sociology, a full on assault of any and all type of social mechanism theory, is indication of how much he heatedly objected to any and all types of social physics, social mechanics, social chemistry, and social thermodynamics. [9] Sorokin, to the end, it seems was anti-physical science, when it came to sociology. In his 1936 presidential address before the Internal Congress of Sociology, in a paper entitled "Le concept d'equilibre: est-il necessaire aux sciences socialies?", Sorokin became very explicit about this: [19]

“Equilibrium appears to me inadequate and represents a liability rather than an asset in the social sciences, and for this reason, should be dropped rather than used in these disciplines. We must cut short this imitation of the physico-chemical, and even in part biological, sciences, we must acquire the autonomy to speak a language which is not distorted by borrowings from the other natural sciences.”

The only person who would seem to comes close to Sorokin, in his heated rage against the physical science based sociologies, is Austrian sociologist Werner Stark (1962). [10]

It would have been quite a sight to see, Henderson and Sorokin going head to head, to say the least. The battle would have amounted, as an approximate estimate, to a physicochemical mechanism bulldog (Henderson) going against a vitalism bulldog (Sorokin); though, to note, it remains to be discerned to what exactly Sorokin was so vehemently objective about, whether it be the “mechanism-vitalism alteration and the theory of abiogenesis” as Robert Merton (1933) communicated with Sorokin about, whether it was some type of hidden religious or free will objection, or whether it had to do with bubbling hatred of the historical materialism of the Karl Marx variety, being that Sorokin, prior to becoming the founding chairman of the Harvard sociology department, was imprisoned three times by the Czarists, three times by the Bolsheviks, and released from the death sentence by Vladimir Lenin himself (Ѻ); or possibly it was another issue yet to be discerned.

The book proposal referred to above by Homans, to note, resulted in the 1934 An Introduction to Pareto: His Sociology. [8]


Edwin Wilson (1879-1964)	Joseph Schumpeter (1883-1950)	Paul Samuelson (1915-2009)
In the 1930s, at Harvard, American polymath Edwin Wilson taught a physical chemistry based economics course, the nature of which he discussed via letter exchanges with Joseph Schumpeter, the product of which was American economist Paul Samuelson, to took these ideas to heart, in the writing of his economics theories.

Wilson | Schumpeter | Samuelson
In any event, on 23 Mar 1934, American mathematician Edwin Wilson, the famous sole protégé of Willard Gibbs, wrote to Harvard economics chairman Harold Burbank, the following: [6]

“I should not attempt to teach economics but simply mathematical economics, which in many respects is a different thing. I couldn’t teach the steam engine, but I have taught thermodynamics and the analogy is about the same.”

Wilson’s course for economics, described here, as Weintraub speculates, was “most probably a course either taken by Samuelson or whose readings were studied by Samuelson.”

Burbank, to note, was the one who would later deny Paul Samuelson a position at Harvard, because he disliked people who were “smart, Jewish, or Keynesian”, as Samuelson's colleague Robert Solow commented, had an intense aversion to mathematical economics, and would later order the hand-set plates to Samuelson’s prize winning dissertation destroyed after 1,500 copies, meaning that no revisions would be possible for the next 35-years.

On 19 May 1937, Austrian-born American economist Joseph Schumpeter gave the following opinion to Wilson in letter: [12]

“I perfectly agree with those who object to the practice of some economists, simply to copy out what they believe is an economic argument from textbooks of pure or theoretical mechanics or physics, and I hope you will not interpret what I am to say in the sense of that practice … We must not copy out actual arguments but we can learn from physics how to build up an exact argument. Most important of all is the consideration that there are obviously a set of concepts and procedures which, although belonging not to the field of pure mathematics but to the field of more or less applied mathematics, one of so general a character as to be applicable to an indefinite number of different fields. The concepts of potential, or friction or inertia are of that kind.”

In 1938, Wilson communicated the following to Burbank in letter:

“Schumpeter has suggested that it would be particularly well for me to give as I gave last time a general theory of equilibrium such as this is understood by physical chemists including the phase systems of Willard Gibbs. Most of our equilibrium theory in economics really has for its background the notions of equilibrium which arise in mechanics. Although Pareto was certainly quite familiar with the types of equilibrium which arise in physical chemistry and are necessary in fact for the study of the steam engine he doesn’t use this line of though in economics.”

Here, to clarify, while it is true that Pareto, in his Treatise on General Sociology, did use the term “chemistry” on 41 pages and “thermodynamics” on 16 various pages, he only uses or rather grapples with the more complex term "entropy" once, namely in the fourth volume, which is the key term one would have to grapple with if he or she was so inclined to attempt to reformulate the general equilibrium theory of economics in "thoroughly thermodynamic terms", as American science historian Hunter Heyck (2005) seems to intuit. [11] In short, Wilson, in his assertion that Pareto, in the 1910s drafting period of his treatise, was “quite familiar with the types of equilibrium which arise in physical chemistry”, is a bit overzealous; physical chemistry was barely a field at this time, and modern equilibrium chemical thermodynamics would not arise until the decades to follow 1923, when Gilbert Lewis published his thermodynamics textbook, making Gibbs work available to chemists as a tool.

Of note, as Weintraub points out, Wilson, the same day in 1938, also writes the following to Pitirim Sorokin:

“It has always seemed to me that the analogies used by people in the social sciences which were drawn from physics were limited to mechanics. In the early days physical chemistry was treated on the analogy to mechanics and the treatment was most often awkward and ignored some of the most striking phenomena. It was only with the slow infiltration of Gibbs’ notion about the phases into the general teach about physical chemistry that physical chemists came to extend equilibria and quasi-equilibria on a broader basis than they could be understood form mechanical analogies. I am inclined to believe that sometime in the discussion of social phenomena it [may be] necessary to have some concepts even more general than that of the phase system.”

Ten days later, Wilson wrote the following to Samuelson with critical comments on a paper by Samuelson:

“Moreover, general as the treatment is I think that there is the possibility that it is not so general in some respects as Willard Gibbs would have desired. [In] discussing equilibrium and displacements from one position of equilibrium to another position [Gibbs] laid great stress on the fact that one had to remain within the limits of stability. Now if one wishes to postulate the derivatives including the second derivatives in an absolutely definite quadratic form one doesn’t need to talk about the limits of stability because the definiteness of the quadratic form means that one has stability. I wonder whether you can’t make it clearer or can’t come nearer following the general line of ideas [that] Gibbs has given in his Equilibrium of Heterogeneous Substances, equation 133.”

The very impressive mention of "equation 133", from Gibbs' subsection "Internal Stability of Homogeneous Fluids as indicated by Fundamental Equations", is the following:

$U - TS + PV - M_1 m_1 - M_2 m_2 ... - M_n m_n \,$

Wilson, in other words, is suggesting, as it seems to be, to Samuelson that he use the Gibbs fundamental equation to formulate a theory of economic stability. Very hilarious indeed. Even the best of the best top dozen of the three dozen or so known human free energy theorists have been barely able to get a handle on this very intricate problem. No wonder Samuelson, into the 1970s, would become so irritated when people queried him about entropy and or sent him entropy-based economic papers to look at.


The so-called "Gibbs circle in economics", with Irving Fisher at the epicenter, flanked above right by Lawrence Henderson, and clockwise: Jan Tinbergen, Tjalling Koopmans, Lawrence Klein, Paul Samuelson, and Edwin Wilson, all Gibbsian proselytes, according to Samuelson (1989), in that each built their economics models on or via influence of the thermodynamics work of Willard Gibbs. [13]

The so-called "Gibbs circle in economics", with Irving Fisher at the epicenter, flanked above right by Lawrence Henderson, and clockwise: Jan Tinbergen, Tjalling Koopmans, Lawrence Klein, Paul Samuelson, and Edwin Wilson, all Gibbsian proselytes, according to Samuelson (1989), in that each built their economics models on or via influence of the thermodynamics work of Willard Gibbs. [13]

Gibbs circle in economics
Related, in a way, to the so-called Harvard Pareto circle, is what American economist Paul Samuelson referred to as the "Gibbs circle in economics", as follows in the opening page of his 1989 symposium presentation "Gibbs in Economics": [13]

“My title could just as aptly have been: ‘The Gibbs Circle in Economics’. It would of course have begun in New Haven with Irving Fisher at its epicenter. Edwin Wilson, Gibbs’ last protégé, transported his tradition to MIT and Harvard. Lawrence Henderson, Harvard physiologist turned philosopher and zealot for Pareto’s sociology, was not quite an economist but he did proselytized for Gibbsian equilibrium in blood and elites. Wilson was my master, first among equals. Through his lineage I could claim Gibbs as my grandfather; and when my first PhD student Lawrence Klein came to generalize the Le Chatelier’s principle to quadratic forms of statistical variances, this Nobelist could claim rights to the apostolic succession.”

To this group, Samuelson adds in Jan Tinbergen and Tjalling Koopmans as two Nobel laureates in economics who showed Gibbsian Influence. Roy Weintraub, who completed his PhD in mathematical economics under Klein, would also seem to be grouped here.

Quotes
The following are related quotes:

“Pareto’s Trattato di Sociologia Generale [Treatise on General Sociology] is the hardest boiled book I have ever read. Three times, since I passed my puberty, has my mind been made over. Once by a nexus of which Henry Adams was the center, once by a matrix of which Frazer burned brightest, and once by a long study of genetics and evolution. Pareto is doing the job a fourth time, and far more vitally than any others.”
— Bernard DeVoto (1928) [3]

“The circle is completed, and virtually unbroken: Gibbs to Wilson, Gibbs to Henderson, Poincare to Birkhoff, Pareto to Henderson, energetics to Lotka to Wilson—roll them all together in the Harvard of the 1930s, add one young scientifically open-minded Samuelson eager to please his senior fellows, simmer in the Society of Fellows, and the Foundations emerges, contingent as it must be on its contents.”
— Roy Weintraub (1991), On Wilson in respect to the Harvard Pareto circle [6]

“It appears that Homans early involvement with Pareto and the locally influenced ‘Pareto Circle’—along with his own talent and hard work—were the keys to his successful rise at Harvard. Shocking as it may now seem, in 1945 key decision makers felt that Homans’ Pareto-influenced scholarship in English Villagers demonstrated that he was clearly superior over other candidates [e.g. Samuel Stouffer and Robert Merton] for permanency.”
— Lawrence Nichols (2006). “The Rise of Homans at Harvard: Pareto and the English Villagers” [4]

See also
● Epicenter genius | Newton’s circle
● Lewis school | University of California, Berkeley | Lewis’ orbit
● Two cultures synergy

References
1. (a) Heyl, Barbara. (1968). “The Harvard ‘Pareto Circle’.” Journal of the History of the Behavioral Sciences, 4:316-34; in: Talcott Parsons: Critical Assessments, Volume 1 (editor: Peter Hamilton) (§2, pgs. 29-49). Taylor & Francis.
(b) Weintraub, E. Roy. (1991). Stabilizing Dynamics: Constructing Economic Knowledge (pgs. 63-64). Cambridge University Press.
2. Isaac, Joel. (2008). “The Harvard Pareto Circle Revisited” (abs), Seminar in Political Thought and Intellectual History, PolThought.cam.ac.uk.
3. Stegner, Wallace E. (2001). The Uneasy Chair: A Biography of Bernard DeVoto (Pareto, 26+ pgs; course, pg. 82; derivation, pg. 110; §: Seminar on Pareto, pg. 138-43; three times, pg. 138). University of Nebraska Press.
4. Nichols, Lawrence T. (2006). “The Rise of Homans at Harvard: Pareto and the English Villagers”, in: George C. Homans: History, Theory, and Method (editor: A. Javier Trevino) (pgs. 43-62). Paradigm Publishers.
5. Fuller, Steve. (2000). Thomas Kuhn: a Philosophical History of Our Times (Pareto, 13+ pgs; §3.5: The Harvard Strategy for Resisting a New Deal for Science, 162-69; Harvard’s Pareto Circle, pgs. 163-69). University of Chicago Press.
6. Weintraub, E. Roy. (1991). Stabilizing Dynamics: Constructing Economic Knowledge (Wilson letters, pg. 60; also 63-65; circle completed, pgs. 65-66). Cambridge University Press.
7. (a) Homans, George C. (1984). Coming to My Senses: the Autobiography of a Sociologist (pg. 105). Transactions Publishers.
(b) Weintraub, E. Roy. (1991). Stabilizing Dynamics: Constructing Economic Knowledge (pg. 65). Cambridge University Press.
8. Homans, George C. and Curtis, Charles P. (1934). An Introduction to Pareto: His Sociology. Alfred A. Knopf, H. Fertig, 1970.
9. Sorokin, Pitirim. (1928). Contemporary Sociological Theories (§1: The Mechanistic School (pdf), pgs, 4-62; thermodynamics, pgs. 25-27; human molecules, pg. 46-47). Harper & Brothers.
10. Stark, Werner. (1962). The Fundamental Forms of Social Thought. Routledge & Kegan Paul.
11. (a) Pareto, Vilfredo. (1912). The Mind and Society: a Treatise on General Sociology (Volume One) (chemistry, 24+ pgs; thermodynamics, 2+ pgs); (Volume Two) (chemistry, 1+ pgs); (Volume Three) (chemistry, 8+ pgs; thermodynamics, 2+ pgs); (Volume Four) (chemistry, 8+ pgs; thermodynamics, pg. 1461). AMS Press, 1935; Four Volumes Bound as Two: Volume One: Non-Logical Conduct, Volume Two: Theory of Residues. Dover, 1963.
(b) Crowther-Heyck, Hunter. (2005). Herbert A. Simon: the Bounds of Reason in Modern America (pg. 69). JHU Press.
(c) Hunter A. Crowther-Heyck (about) – ACLS.org.
12. (a) Schumpeter, Joseph. (1937). “Letter to Edwin Wilson”, May 19; in: Harvard University Archives, Wilson Correspondence, HUG 4878.203.
(b) Mirowski, Philip. (1989). More Heat than Light: Economics as Social Physics, Physics as Nature’s Economics (pg. 354). Cambridge University Press.
13. Samuelson, Paul. (1989). “Gibbs in economics”, in: Proceedings of the Gibbs Symposium, Yale University, May 15-17 (editors: D.G. Caldi and George Mostow) (pgs. 255-68; Gibbs circle in economics, pg. 255). American Mathematical Society.
14. Russett, Cynthia. (1966). The Concept of Equilibrium in American Social Thought (pgs. 141-42). Yale College.
15. Burrell, Gibson. (1999). “Normal Science, Paradigms, Metaphors, Discourses and Genealogies of Analysis”, in: Studying Organization: Theory and Method, Part 1 (editors: Stewart Clegg and Cynthia Hardy) (§16, pgs. 388-). Sage.
16. Heyl, Barbara. (1968). “The Harvard ‘Pareto Circle’.” Journal of the History of the Behavioral Sciences, 4:316-34; in: Talcott Parsons: Critical Assessments, Volume 1 (editor: Peter Hamilton) (§2, pgs. 29-49). Taylor & Francis.
17. Thims, Libb. (2013). “Econoengineering and Economic Behavior: Particle, Atom, Molecule, or Agent Models?” (video, 1:33-min) (article, 40-pgs) (PowerPoint, 36-slides), Key speaker talk delivered at the University of Pitesti Econophysics and Sociophysics Workshop (UPESW) / Exploratory Domains of Econophysics News (EDEN V) (organizer: Gheorghe Savoiu). University of Pitesti, Pitesti, Romania, Jun 29.
18. Lopreato, Joseph and Rusher, Sandra. (1983). “Vilfredo Pareto’s Influence on USA Sociology” (abs), Revue Europenne des Sciences Sociales, 21(65):69-122; in: Vilfredo Pareto: Critical Assessments of Leading Economists, Volume 3 (editors: John Wood and Michael McLure) (§74, pgs. 187-237). Taylor & Francis, 1999.
19. (a) Sorokin, Pitirim. (1936). "Le concept d'equilibre: est-il necessaire aux sciences socialies?", presidential address before the Internal Congress of Sociology, in: Social and Cultural Dynamics, vol 4, pg. 677.
(b) Russett, Cynthia. (1966). The Concept of Equilibrium in American Social Thought (pgs. 131). Yale College.
20. (a) Mayo, Elton. (1933). The Human Problems of an Industrial Civilization (pg. 28). Cambridge University Press.
(b) Russett, Cynthia. (1966). The Concept of Equilibrium in American Social Thought (pgs. 143). Yale College.
21. (a) Chapple, Eliot D. and Côôn , Carleton S. (1942). Principles of Anthropology (pg. 361; states of equilibrium, pgs. 695-96). Publisher.
(b) Russett, Cynthia. (1966). The Concept of Equilibrium in American Social Thought (pgs. 143, 148). Yale College.
22. (a) Parsons, Talcott. (1951). The Social System (equilibria, pg. 483; denial, pg. 339). Routledge, 2013.
(b) Russett, Cynthia. (1966). The Concept of Equilibrium in American Social Thought (pgs. 144-45). Yale College.
23. Skinner, Burrhus F. (1977). “Preface: George C. Homans at Harvard”, in: Behavioral Theory in Sociology: Essays in Honor of George C. Homans (pgs. 7-8). Transactions Publishers.
24. Isaac, Joel. (2012). Working Knowledge: Making the Human Sciences from Parsons to Kuhn (§2: The Harvard Pareto Circle, pgs. 63-91). Harvard University Press.
25. Young, Robert M. (1971). “Mystifications in the ‘Scientific’ Foundations of Sociology”, Science or Society?: Bulletin of the Cambridge Society for Social Responsibility in Science,2:9-11, Jun.

Further reading
● Keller, Robert T. (1984). “The Harvard ‘Pareto Circle’ and the Historical Development of Organization Theory” (abs), Journal of Management, 10(2): 193-204.
● Thanem, Torkild. (2011). The Monstrous Organization (§: The Harvard Pareto Circle, pgs. 14-15; §: L.J. Henderson’s Physical and Social System, pgs. 16-17). Edward Elgar Publishing.