Peter Turchin is one of the leading minds behind cliodynamics, an effort to make the study of history a fully scientific discipline with the same sort of theoretical and mathematical rigor that under-girds modern scholarship in disciplines like ecology or evolutionary biology. In a 2008 essay written for Nature he justified this project in the following terms:
What caused the collapse of the Roman Empire? More than 200 explanations have been proposed, but there is no consensus about which explanations are plausible and which should be rejected. This situation is as risible as if, in physics, phlogiston theory and thermodynamics coexisted on equal terms. This state of affairs is holding us back. We invest in medical science to preserve the health of our bodies, and in environmental science to maintain the health of ecosystems. Yet our understanding of what makes societies healthy is in the pre-scientific stage.
Sociology that focuses on the past few years or decades is important. In addition, we need a historical social science, because processes that operate over long timescales can affect the health of societies. It is time for history to become an analytical, and even a predictive, science…. Rather than trying to reform the historical profession, perhaps we need an entirely new discipline: theoretical historical social science. We could call this ‘cliodynamics’, from Clio, the muse of history, and dynamics, the study of temporally varying processes and the search for causal mechanisms Let history continue to focus on the particular. Cliodynamics, meanwhile, will develop unifying theories and test them with data generated by history, archaeology and specialized disciplines such as numismatics (the study of ancient coins). 
I commend the intentions of this project and have been impressed with the research it has produced thusfar. However, I remain skeptical that it will ever be able to dethrone the messy, unscientific narratives most historians use to describe trends in macro-history. In particular, I doubt our ability to ever produce convincing, predicative models of cultural change.
|Image Source: Fig 1 from Justin Mcarthy,
“Record 60% of Americans Support Same-Sex Marriage,“
Gallup (19 May 2015)
Americans have witnessed a rather dramatic example of cultural change quite recently. On June 26th, 2015 same-sex marriage became the official law of the land in the United States of America. Many have marveled at the rapid shifts in public opinion that made this possible. As late as 1995, less than 27% of Americans believed same-sex unions should be recognized legitimate unions; a bit more than 60% do today. Younger generations support for same-sex marriage is even more lopsided. This astonishing cultural transformation begs explanation.
An important part of the puzzle is found in popular attitudes about the purpose of marriage and its role in society generally. These attitudes have changed dramatically. A 2010 report from the National Marriage Council does an excellent job describing these changes and some of their social implications:
Over the last four decades, many Americans have moved away from identifying with an “institutional” model of marriage, which seeks to integrate sex, parenthood, economic cooperation, and emotional intimacy in a permanent union. This model has been overwritten by the “soul mate” model, which sees marriage as primarily a couple-centered vehicle for personal growth, emotional intimacy, and shared consumption that depends for its survival on the happiness of both spouses. Thus where marriage used to serve as the gateway to responsible adulthood, it has come to be increasingly seen as a capstone of sorts that signals couples have arrived, both financially and emotionally—or are on the cusp of arriving.
Although this newer model of marriage—and the new norms associated with it—has affected all Americans, it poses unique challenges to poor and Middle American adults. One problem with this newer model—which sets a high financial and emotional bar for marriage—is that many poor and Middle American couples now believe that they do not have the requisite emotional and economic resources to get or stay married. By contrast, poor and Middle Americans of a generation or two ago would have identified with the institutional model of marriage and been markedly more likely to get and stay married, even if they did not have much money or a consistently good relationship. They made do.
But their children and grandchildren are much less likely to accept less-than-ideal relationships. And because infidelity, substance abuse, and unplanned pregnancies are more common in Middle America than they are in upscale America, Middle Americans are less likely than their better-educated peers to experience high-quality soul-mate relationships and are, hence, less likely to get and stay married. Their standards for marriage have increased, but their ability to achieve those standards has not. 
As Ross Douthat has pointed out, same-sex marriage fits into the old “institutional” conception marriage only with great difficulty, but it is a natural consequence—indeed, a paramount example—of the new “soul-mate” model. This new conception of marriage cannot offer any logical reproof to same sex unions (nor does it, for that matter, offer any reasonable objection to polyamorous relationships). Once the new model became orthodoxy it was simply a matter of time before previously heterodox relationships of these sorts were accepted. Same sex marriage was simply a very high profile and contentious marker of this much deeper change change.
But why did this change happen? How do we account for a large reversals in popular attitudes towards the purpose and social roles of families and marriage?
This is not the first time sweeping change of this sort has washed over American society. You would not know this from the way people talk about marriage and family today. Indeed, the most frustrating thing about the Culture War debates of our time is the lack of historical awareness on the part of debaters. Conservatives seldom know the historical origin of the institutions and practices they defend. Progressives, for their part, are even more historically stunted: their narratives of change and progress a rarely stretch back past their days of youthful activism in the 1960s. But we must look back much further into the past than this to see where the “institutional” ideal of marriage and family life comes from. It is approximately two centuries old. The ideal the National Marriage Council labels “institutional”—and which conservatives simply call “traditional”—was created between 1770 and 1830 among New England’s bourgeoisie. By the end of the nineteenth century it provided the standard vision of family life for men and women across America.
In their excellent book Domestic Revolutions: a Social History of American Family Life Steven Mintz and Susan Kellog call this model of family and marriage relations “the Democratic Family.” Its basic features will sound familiar: as an institution marriage was designed to provide love and companionship for both spouses and a nurturing and safe environment for rearing children. Marriage partners were chosen carefully by the future spouses themselves, not by their parents or extended families. Husbands and wives were expected to act as an equal partnership, though each was responsible for sharply differentiated social spheres. Men worked outside of the home itself, acting as the family’s primary breadwinners. Family and home life were conceptualized as a “haven” and resting place from the pressures of that outside world. In the domestic sphere the wife reigned supreme; she was expected to cultivate the sort of warm, loving home environment mentioned above, as well as be the primary care taker and nurturer of the children.
Children were to be nurtured. Through the good example and patient instruction of the parents—especially the mother—each child’s individual talents and abilities could be found and developed. By the same careful and loving methods their character could be refined and improved. Children would be few. They would be treasured. Most importantly of all, they would be treated as children—not as miniature adults or unthinking beasts—until they reached adolescence. They were supposed to feel the same sense of warmth, love and respect for their parents that their parents were expected to feel for each other. They were considered autonomous individuals whose own personality traits and desires, not their family name or background, was at the core of their identity. At a comparatively early age they would separate from their parents completely to establish their own independent household. 
This vision of family life seems familiar to us because it persisted with few rivals right up to through the 1960s. It did evolve in that time (the most serious change occurring during the 30s and 40s, when the category of what we now call “teenager” first developed) but most changes were gradual, and the the basic tenets of family life in the century between the civil war and the civil rights movement were essentially the same. But if the sexual revolution was a sharp transition away from the Democratic Family of old, the Democratic Family itself was just as sharp a transition away from the pattern of familial relations that came before it. New England life was then dominated by the Puritan family. The type of family relations championed by the Puritans couldn’t be more different from the “traditional family values” that dominated American society over the last two centuries.
In Puritan New England, the decision to marry was an economic one which husband, wife, and their families would haggle over. Marriage was understood as a “union where a man provided financial support in exchange for domestic service.” The hierarchy between husband and wife was thus not altogether different from that which separated a man from his servants. Affection between spouses would develop after marriage, if it developed at all. The purpose of a wife was domestic industry, and the family’s wealth was just as a much a product of her labors as that of her husband’s. Families would have far more children than in later times, but “child rearing was not the family’s main function; the care and nurture of children were subordinate to the family’s other interests.” We moderns would be not call Puritan parenting nurturing at all: “in their view the primary task of child rearing was to break down a child’s sinful will and internalize respect for divinity.” This task was given to fathers, not mothers. It ended by the age of seven, “when boys adopted adult clothing, were prevented from sleeping any longer with their sisters or female servants,” and were “fostered out as indentured servants, apprentices, or in rare cases, sent to boarding schools.” For all intents and purposes the Puritan was no longer treated as a child at this point, but simply as a “little adult.” However, the father still wielded immense authority over his children; “Puritan children were dependent on their father’s support in order to marry and set up independent households,” and their fathers possessed a legal right to deny their children’s choice of spouse and retained legal authority over their son’s farms and lands until their death. 
I explain the old Puritan practices and ideals at such length so that readers may get a sense of just how alien their social world is to modern sensibilities. It would have been just as alien to most Americans from any period of this country’s independent history. Modern children can open up domestic children’s novels written in nineteenth century like Laura Ingalls Wilder’s Little House in the Big Woods or Louisa May Alcott’s Little Women and instantly recognize families whose ideals and patterns of life are much like their own. There is no undue sense of culture shock, nor is there a need for long footnotes or introductions to make the social worlds of Josephine March or Laura Ingalls comprehensible. The same could not be said for a novel about family life written a century earlier—though par my point, such a novel would never have been written. Books written specifically for children would have made no sense to the Puritan mind, and as most women were illiterate, it would be hard to find a woman of Alcott’s talents to write one. This past truly was a different country. It took a titanic change in popular attitudes before today’s ‘traditional family values’ could come into being.
Those familiar with the broad span of global history will recognize that these rapid and dramatic changes in attitudes and practices within family life have happened many times before. Often—as was the case in Southern Song dynasty China or is the case in many parts of the contemporary Middle East—these changes would be considered regressive by the standards of 21st century liberals. Yet despite the great variety of family regimes history has given us to examine, we have not been able to create a compelling theory that explains why certain family practices and attitudes persist or change over time. Some parts of this puzzle are fairly well understood—demographers have posited and provided overwhelming evidence for what they term “Demographic Transition Theory,” which describes average fertility rates mostly as a function of GDP per capita and the level of education available to women. But while economic and demographic conditions can largely explain how many children couples across the world have, it cannot explain what they expect from these children or what they think is the proper way to parent them. Today countries with fairly similar economic and demographic profiles—such as much of Western Europe and Japan—have very different attitudes and expectations for the roles men, women, and children are supposed to play in family life. Things like the age at which children leave the home or marry can be quantified and coded with ease. It is much harder to quantify or code how much affection husbands are expected to show their wives, or how harshly parents should discipline their children. 
So what does explain these things? And more importantly, how can we verify if any proposed explanation is true? Is it possible to establish a science of family life?
Families are an interesting object of study, because they are at once a demographic unit, an economic partnership, and set of human relationships that have great cultural meaning. Historians who study families of the past tend to focus one of these three parts, describing change in terms of demographic structure, economic survival strategy, or cultural values. This post concerns the last of these. So that we don’t get bogged down in debates over demographics and economics, it might be helpful to consider shifts in cultural values and attitudes that happened outside of the family entirely. Consider the changes in popular culture Brendan Bruce discusses in his 2013 book, The Origins of ‘Spin’:
The development of the sound bite is closely aligned to the process “dumbing down’ television, which started almost immediately…. In 1955 15 million people paid to attend major league baseball games, while 35 million paid to attend classical music concerts. The New York Metropolitan Opera’s Saturday afternoon radio broadcast drew a listenership of 15 million out of an overall population of 165 million. As the sociologist David White has noted, NBC spent $500,000 in 1956 to present a three-hour version of Shakespeare’s Richard III starring Sir Laurence Olivier. The broadcast drew 50 million mowers; as many as 25 million watched all three hours. White also went on to note that on March 16, I956, a Sunday chosen at random, the viewer could have seen a discussion of the life and times Toulouse-Lauflec by three prominent art critics, an interview with theologian Paul Tillieh, an adaptation of Walter Van Tilburg Clark’s Hook, a documentary on mental illness with Dr. William Menninger, and a 90-minute performance of The Taming of the Shrew. It was not to last.
In 1968, when television still had Murrow-like pretensions to be in the news business, the average length given over to a politician’s reply to a question, or an excerpt from a speech, was 42.3 seconds. Fully 21 percent of these sound bites ran for at least a minute. In 1972 it was 25.2 seconds. By 1976 it had reduced to 18.2 seconds and in 1980 was down again to 12.2 seconds. In 1984 it was down yet again – this time to 9.9 seconds. In 1988 it reduced to 9.8 seconds; in 1992 to 8.2; and in 1996 to 7 seconds. 18 seconds in twenty five years. The press equivalent – the ‘ink bite’- has reduced over time from 14 column lines to six. 
Mr. Bruce presents compelling evidence that both American political culture and American popular culture has been “dumbed down” over the last sixty years. Anyone who has watched game shows or news programs from the era Bruce extols, or has read through the archives of magazines like Time, Life, Newsweek, or Foreign Affairs can attest that American information culture has become more vulgar, less erudite, and geared towards smaller and smaller attention spans during this time.
I discussed this passage in a private exchange with Adam Elkus, blogger at Rethinking Security and Zero Derp Thirty several weeks ago. Over the course of our exchange we came up with nine different plausible explanations for why this “dumbing down” of popular media might have happened. In the weeks since then I have developed another three potentials explanations for the trend. But this is precisely the problem. As it stands now, discussions of cultural change are no different than the discussions of Rome’s decline that distress Peter Turchin. It is easy to create a story that explains why Americans have grown less articulate and formal over the last few decades, or why their expectations for marriage have changed. It is difficult to prove which of these stories is correct. We simply don’t have the methodological tools we need to scientifically test one hypothesis over the other.
I am unsure this will ever change. A central problem is that many cultural values and meanings at play here are too nuanced to be coded or quantified, and thus hypotheses built on them are quite difficult to falsify. To a great extent this explains why obscurist, ideology-heavy, “critical theory” interpretations of culture hold so much sway over much of the humanities. To outsiders looking in these interpretations are obvious foolishness, but until there is a science of cultural change capable of falsifying these interpretations, the study of culture will remain a morass where nothing but academic fashion and popular opinion can privilege one explanation over another.
 Peter Turchin, “Arise ‘cliodynamics’,” Nature 454, iss 3 (2008), 34-35.
 Brad Wilcox, ed., When Marriage Disappears: Retreat From Marriage in Middle America (State of our Unions 2010) (Charlottesville, VA: National Marriage Project), 38-39.
 Susan Kellogg and Steven Mintz, Domestic Revolutions: A Social History of American Family Life, (New York: The Free Press, 1988),43-67.
 ibid., 1-23. Quotations from 9, 14-17, 58.
 It is also worth noting that–contrary to the claim that changes in marriage and family ideals are purely a function of economic realities–the current shift from “institutional” to “soul-mate” models of marriage has carried heavy economic costs for most of American society. Economic survival models of family structure struggle to explain the rise of the “soul-mate” model of marriage. See note 2.
 Bruce Brendan, On the Origin of Spin: Or how Hollywood, the Ad Men and the World Wide Web became the Fifth Estate and created our images of power (CreateSpace Independent Publishing Platform, 2013); 249.