|A basic visual of "social entropy", i.e. entropy applied sociologically, namely that from the sum of all the entropy (dQ/T) differentials going into or out of a system, where "a quantity of heat absorbed by a changing body is positive, and a quantity of heat given off by it is negative, for cyclical processes where the changes occur in a non-reversible manner" (Clausius inequality, 1865), must equal the negative of the equivalence value of all uncompensated transformations (-N), per 1856 definition of entropy, or be less than or equal to zero, per 1865 definition of entropy.|
Note | Confusion
Two main salient, albeit oft-unstated, aspects of confusion surrounds "entropy", in its original universal formulation by Clausius (1854/1865) (see: entropy etymology), extrapolated to social systems. Firstly, entropy, in some specifically defined processes (e.g. adding heat to an ice cube) entropy increase can be correlated to a molecular disorder increase. This, however, is not a universal definition or model of entropy. The following is a typical example of confusion:
“To the layman, the second law of thermodynamics states that over time systems become more ‘disordered’. Does sociology have anything to say about this? Do societies tend to become more disordered over time as well?”— NWH (2013), PhysicsForums.com post (Ѻ), Feb 26
The second law, in short, does not say that all systems tend towards disorder over time. This is what is called laymanized thermodynamics gone wrong; a result of simplified explanations taken as fundamental explanations.
Secondly, entropy, per the infamous 1941 joke suggestion of John Neumann (see: Neumann-Shannon anecdote), entropy is often taken as a measure of information, in the binary number, Boolean operator, computer science sense of things, which is a mathematical isomorphism, and therefore not fundamentally correct, in a thermodynamic sense. 
Social entropy, in oft-used colloquial sense, refers to manifestations of entropy, defined as the amount of energy unavailable for doing work in a given process, in a given social system, distinguished by modes of negative behaviors, specifically alienation, anomie, and deviance, that function to instill a disordering effect in a given social structure or order.  These anomalous behaviors are seen as withholdings or cross uses of the deviant manifestations of the human energies that normally go into support or fulfillment of the norms, roles, and statuses that make up a social order.
In 1874, Peter Tait, during an address to graduating arts students of Edinburgh University, gave the earliest English usage coinage of the term “social entropy” as follows: 
“The application of these ideas [of second law energy degradation] to political and social questions, among which of course comes university centralization, is not far to seek. What would the world of men be without what we may call ‘social entropy’? Everyone would then be his own farmer, baker, butcher, brewer, banker, boot-black, &c.—all would be at the same dead level [see: heat death]—no possible help from one to his neighbor, even if it could be required; no distribution of tasks, and therefore (in every department) that endless waste which is inevitable in operations conducted on a petty scale. No possibility of that mutual reliance and assistance which forms the friendships we delight in, none of that variety which is the real charm of life—no idea which would not simultaneously strike every unit of the race—no news, no books—nothing but sameness! None of the pleasure of being able to assist struggling worth, none of gratitude for generous aid. Nay, we might pursue it further. No difference of temper, character, tendencies, age, sex—a state lower than the lowest known in vegetation; but here the end must come. Or, to take a somewhat different point of view (though the basis is absolutely the same, for oscillation implies entropy), what if everything were always at its average value? Never absolutely either fair or rainy weather, clear or cloudy, calm or stormy, hot or cold; but a dead average. Never either absolutely day or night; no tides, no seasons; men never either absolutely awake nor absolutely asleep—continually in a semi-lethargic state— half happy, hall discontented; half playful, half serious— neither running, walking, standing, sitting, nor lying, but a perpetual average. No catastrophes such as a birth, a marriage, or a death —no distinction between man and man—nothing of that variety which is the law of nature. Eternal, hideous, intolerable sameness, by necessity devoid of all capacity for action: the human race turned into a set of Nurnberg toy-solders, all cast in the same mould, of the same base material, and all similarly bedaubed from the same glaring paint-pots, and moving on the same lazy-tongs with the same relative velocities. No one to advise you in a difficulty, no one in whose superior strength of mind or body you could confide; nothing around you except what you feel must be but the image of yourself (as you will early have learned introspectively to look at it)—mean, sordid, and groveling! No one whom you can respect, none to trust—all, like yourself, vile and despicable! II ere I would gladly say—' Enough of such horrors,' and quit the disgusting theme. But, unfortunately, the application has still to come. It will be found very pertinent to many things which have been of late evolved from the innermost consciousness of statecraft, and hailed, with altogether inexplicable delight, by what seemed (till lately) to be at least a numerical majority of the representatives of our countrymen.”
Here, we note that Tait seems to be using the William Thomson model of the second law, which is not fully correct, in a universal sense, and not the same as entropy, defined by Clausius; we also note that Tait himself did not have a correct understanding of entropy, as evidenced by James Maxwell had to “correct” the fourth edition of his Theory of Heat, to fix the erroneous model of entropy he had previous learned from Tait (see: entropy misunderstandings).
In 1894, Leon Winiarski, of the so-called “mechanistic school”, in the lectures to his Essay on Social Mechanics, gave the first equation based usage of entropy, e.g. the Clausius inequality, applied sociologically; this would seem to be the most dominate example of entropy used in sociology.
The etymology of the term "social entropy", used in a significant sense, for modeling purposes, according to Robert Nisbet (1970), is said to trace back to the 1890s to 1900s work of philosopher-historians Brooks Adams and Henry Adams who applied the concept of entropy to human affairs, viewing it as a tendency seen in the histories of whole nations or civilizations, a tendency characterized by a running-down of human energy, of a diminished capacity for meeting the problems set by that nation or civilization. 
In 1934, Joseph Unwin, in his Sex and Culture, was theorizing about "human entropy" in the context of social sexual restraints; Aldous Huxley (1938) summarized Unwin's views as follows:
“Where productive energy persists for some time, a factor which Unwin calls ‘human entropy’ comes into play. Human entropy is the inherent tendency, manifested as soon as the suitable social conditions are created, towards increased refinement and accuracy. ‘No society can display productive social energy unless a new generation inherits a social system under which sexual opportunity is reduced to a minimum. If such a system be preserved a richer and yet richer tradition will be created, refined by human entropy’.”
In 1968, Amitai Etzioni described "social entropy" as a state of society in which no social bonds are present. 
In 1986, Klaus Krippendorff, in his Entropy, Diversity, and Variety (Ѻ), was defining entropy, albeit in the information theory context, as “a measure of observational variety or of actual (as opposed to logically possible) diversity.” Krippendorff defined social entropy as a measure of the natural decay of the structure or of the disappearance of distinctions within a social system. He reasons that much of the energy consumed by a social organization is spent to maintain its structure, counteracting social entropy, e.g., through legal institutions, education, the normative consequences or television, and that anomie is the maximum state of social entropy. 
In 1990, American sociologist Kenneth Bailey published Social Entropy Theory, a nonequilibrium approach of societal analysis using a mix of Ludwig Bertalanffy's general systems theory, Claude Shannon's entropy, and Rudolf Clausius' entropy. Bailey defines an "isomorphic complex system" as being comprised of human individuals as the components, interaction of these components, and the national (political) border of the country, with the latter serving as a boundary for social interaction.  Bailey also included a section titled the "History of Social Entropy", in which he traces the use of thermodynamics and entropy in sociology from Pareto to Prigogine to Samuelson and others in the literature. 
In 2001, Peruvian engineer Alfredo Infante wrote a short article entitled "Social Entropy" in which he discussed the advanced intelligence perspective, Gibbs free energy, among other topics. 
In 2008, American physical chemist Thomas Wallace argued that "societal entropy", as determined by the second law, mandates the spontaneous direction of all processes of nature and society and the generation of greater complexity and disorder. 
Social entropy is said to be one of the elements or components of the social bond, which, according to American sociologist Robert Nisbet, mediates a part of the force that enables "biologically derived human beings to stick together in the social molecules (human molecular aggregates) in which we actually find them from the moment, quite literally, of their conception. 
1. Nisbet, Robert A. (1970). The Social Bond - an Introduction to the Study of Society, (ch. 10: "Social Entropy", pgs. 260-98). New York: Alfred A. Knoph.
2. Nisbert, Robert, A. (1970). The Social Bond - an Introduction to the Study of Society, (ch. 3: "The Nature of the Social Bond", pgs. 45-56). New York: Alfred A. Knoph.
3. Etzioni, Amitai. (1968). The Active Society - a Theory of Societal and Political Processes (pg. 95). Free Press.
4. Bailey, Kenneth D. (1990). Social Entropy Theory, (ch. 3: "Social Entropy", pgs. 49-87; "The History of Social Entropy", pgs. 71-87). Albany, N.Y.: State University of New York Press.
5. Social Entropy - Klaus Krippendorff's Dictionary of Cybernetics.
6. Wallace, Thomas P. (2009). Wealth, Energy, and Human Values: the Dynamics of Decaying Civilizations from Ancient Greece to America (pg. xi). AuthorHouse.
7. Infante, Alfredo, P. & Lawler, James, H.L. (2001). “Social Entropy”. The Nexial Institute.
8. Thims, Libb. (2012). “Thermodynamics ≠ Information Theory: Science’s Greatest Sokal Affair” (Ѻ), Journal of Human Thermodynamics, 8(1): 1-120, Dec 19.
9. Tait, Peter. (1874). “Commencement Ceremony Talk on capping the graduates in arts of Edinburgh University” (Ѻ), Apr 22; in: Nature (pg. 502-03), Apr 30.
● Balch, T. (2000). “Hierarchical Social Entropy: an Information Theoretic Measure of Robot Group Diversity.” Autonomous Robots, 8, pgs. 209-237.
● Matei, Sorin A. (2008). “A Social Entropy Vision of Wiki Collaboration”, Matei.org, I Think, Dec. 12.
● Matei, Sorin A., Oh, Kyoungrae, Bruno, Robert. (2008). “Collaboration and Communication in Online Environments: A Social Entropy Approach” (28-pgs). Purdue University.
● Bailey, Kenneth D. (1981). “Entropy Measures of Inequality: an Application of Social Entropy Theory”, Paper presented at the annual meeting of Society for the Prevention of Social Problems. 38-pages.
● Bailey, Kenneth D. (1983). “Sociological Entropy Theory: Towards a Statistical and Verbal Congruence.” Quality and Quantity, 18: 113-33.
The following are articles that cite and or heavily rely on this Hmolpedia article:
● Bera, S. and Acharjee, S.K. (2013). “Estimation of Social Entropy: the Dictum of NEO Modernism in Agricultural Knowledge Environment in India” (pdf), International Journal of Agriculture and Food Science, 4(10):989-98.
● Riva, Adam. (2018). “#10 Justin Deschamps | The Psychological Mechanism of Social Entropy” (Ѻ), Dauntless Dialogue, Jun 10.
● Social entropy – Wikipedia.