Conflict between siblings is a more significant force in human history than class struggle, according to Frank Sulloway, a Harvard psychologist. He believes that first borns tend to be conformist and younger siblings rebellious-and offers a pile of statistics to support his case. Matt Ridley is intrigued but scepticalby Matt Ridley / November 20, 1996 / Leave a comment
Liberte, egalite, fraternite!” However successful the French revolution may have been at generating liberty and equality, it was a terrible failure at the practice of fraternity. Not only did real brothers find themselves divided against each other by the revolution, but ideological brothers-in-arms guillotined each other with relish. The Terror of 1793 is often described as “fratricidal.”
This description may be closer to the truth than historians have realised. The battles between the Girondin and the Montagnard deputies to the National Convention, which led to the Terror when the Montagnards gained the upper hand, was largely a battle between younger and elder brothers. Most of the Girondins were younger children in their families, and most of the Montagnards, elder.
Indeed, among the deputies were 16 real brothers who grew up together, including Maximilien and Augustin Robespierre. No younger brother sat to the left of his elder brother, the left being the side of the hall associated with greater extremism and repression. Here then is a new history of the French revolution: royalist elder brothers were overthrown by progressively more younger-child revolutionaries until 1793 when elder brothers grabbed back power in the violent coup of the Terror. The tolerant interlude of 1789-92 was characteristic of a period of rule by younger brothers.
A new and curious insight, or farcical sociological simplification? This analysis comes from a new book, Born to Rebel (Little, Brown), by Frank Sulloway, published in November. Sulloway is neither a sociologist, nor a professional historian. He is a psychologist at Harvard, and an odd one at that because he is a closer disciple of Charles Darwin than Sigmund Freud (although he has written a biography of Freud). His book is a long exploration of the idea that a Darwinian understanding of sibling conflict explains a great deal of human history, politics and sociology.
Of the French revolution, he writes, “Sibling strife, not class conflict, lay at the heart of the Terror. The ultimate failure of the French revolution resided in the participants’ inability to grasp this fact.”
Sulloway’s theory is that radicalism, openness to new ideas and gullibility are generally characteristic of younger siblings, whereas reaction, orthodoxy and intolerance are characteristic of their elder sibs. He demonstrates this with a mountain of statistics taken from several historical revolutions in both science and politics. During the Reformation, for example, he finds that two thirds of Catholic martyrs executed in Protestant countries were eldest children, while an astounding 96 per cent of Protestant martyrs in Catholic countries were younger children.
We are quite used to the idea that age and social class may influence people’s political views, so there should be no difficulty in accepting that birth order matters, too. Sulloway, however, wishes to go further and persuade us that birth order is a much stronger influence than either age or class. In 1520, for instance, a typical 70 year old second born was as likely to be of the new Reformed faith as a 30 year old first born-at least in Sulloway’s sample of historical figures whose views are known. And in the 19th century, argues Sulloway, there was a much stronger correlation between birth order and support for radical evolutionary ideas than there was between social class and views on evolution. Evolution was espoused by wealthy gentleman Darwin (a fifth child out of six) and lower-middle class Alfred Russel Wallace (the eighth of nine children). “Oh what a scheme is primogeniture,” wrote Darwin to Wallace, “for destroying natural selection.”
Sulloway’s theory, if it stands up to scrutiny-and he has amassed astonishing amounts of material over 25 years to support it-is a fascinating attempt to clear the Marxist hangover we all suffer from. History, he says, is not so much about the conflict between classes as about the conflict between siblings.
Although most of his case histories are of men, the same patterns apply among women, and men who are eldest sons but not eldest children still behave largely like later-borns. Gender undoubtedly matters, but an elder sibling is an elder sibling whether male or female. As an example of an inflexible and dogmatic first-born woman, who devoted her life to pursuing the intellectual faith of her mentor and took care not to let facts get in her way, Sulloway cites Margaret Mead, who was virtually a parent to her younger sibs. As an example of a daring and radical later-born woman, he cites Darwin’s brother’s “girlfriend,” Harriet Martineau, the champion of mesmerism and political economy and the person who introduced Darwin to Thomas Malthus’s work. Sulloway also interprets the varying success of Henry VIII’s six wives in keeping their necks intact according to their birth order. “Those wives who lost their heads tended to be late in birth rank and outspoken in their opinions.”
But the effect on history is nothing to the effect Sulloway’s ideas will have on biology. They re-open enthusiastically a stale old debate called nature-nurture. These days, the conventional wisdom on nature-nurture goes like this. It is a false and misleading debate because there is no dichotomy to be easily drawn between somebody’s genes and their environment. Genes are as meaningless without environments as cake recipes are without ovens. The same genes can produce different results in different environments, and the same environments can produce different results if genes differ. Tall people grow tall because of an inextricable mixture of tall genes and good childhood nutrition. A person of medium height might have had medium genes and medium nutrition, tall genes and poor nutrition or short genes and good nutrition.
This little sermon usually precedes a stern injunction to ignore the blandishments of geneticists trying to claim that they have found the gene for some aspect of behaviour. It is utter nonsense, we are told, to say that somebody’s sexuality or violence is the product of their genes, and those who do so are being mischievous or evil. True enough, in many cases. Yet the very same people who write this kind of thing are then happy, sometimes in the very next paragraph, to speculate wildly about the influences of upbringing on personality. Their stern sermons seem to apply to genes but not environments.
This is unjust. A biographer who claimed that his subject was the way he was because of the genes he inherited would be chastised. A biographer who claimed that his subject was the way he was because of his family background would be considered quite normal. Yet we have just heard that nature and nurture are inextricable, and that family backgrounds have different effects on different natures as well as vice versa. It is a widespread double standard. The scandal of the nature-nurture debate is not that the champions of nature claim too much but that the champions of nurture say it is a false dichotomy and then proceed to ignore their own advice.
Into this debate parachutes Frank Sulloway’s theory of birth order. It is a theory of nurture, self-evidently; but it is a theory of nature, too. Sulloway uses the logic of evolutionary adaptation to arrive at his ideas. He argues that people are designed to have natures (genes) which respond to birth order in specific, predictable and universal ways. You have a genetic programme that says, in brief, “if born first, conform; if born last, rebel.”
That programme evolved as part of our natures because it made sense in our distant evolutionary past. It gave eldest children their best chance of hanging on to their natural head start in inheriting the territory or possessions of the parents, and it gave younger children their best chance of avoiding or winning conflict with elder siblings and striking out on their own. That way younger siblings became risk-seeking and elder siblings risk averse. Literally: Sulloway finds that younger children prefer more dangerous sports than elder children.
Sulloway’s ideas are squarely in the mainstream of evolutionary psychology, a Darwinian science that is usually considered very “nature”-obsessed because it searches for evolved, universal human nature rather than emphasising cultural differences. Yet it sees genes very differently from the way most geneticists do. Genes are far more about creating individual similarities than individual differences: similarities in the way people respond to environmental differences. Thus, monkeys have higher serotonin levels in their brains because they are high in social rank not vice versa-a clear case of an external, non-genetic influence. Yet why do their serotonin levels rise when they rise in rank? Because they have genes that instruct cells to produce serotonin in response to cues of high rank.
Sulloway’s theory is a parallel idea. The family, he reckons, contains a series of different niches. The first born’s niche is to align himself with the parents and dominate his younger siblings; the younger child’s niche is to differentiate himself from the eldest by experimenting, diverging and rebelling. Sulloway does not choose to recognise how close he comes to echoing economists on this point, but I think the resemblance of their arguments is remarkable.
Ever since Adam Smith, economists have emphasised the role that the division of labour plays in creating prosperity: the more divided labour is, the more wealth a society can generate-because each person specialising in his own task will produce more than if he has to be self-sufficient in everything. Although many of them do not know this, that is why economists like markets and global free trade. The greater the market, the greater the division of labour it allows. I argue in my new book The Origins of Virtue (published in October by Viking) that so important have divisions of labour been in human history and prehistory that they have left their imprint on our developmental strategies. Unlike virtually all other species, we do not try to be good at everything our species does. From an early age, human beings become specialists in what they find they are good at: tennis playing, mending cars, telling jokes, poring over figures-we can in retrospect discern our own speciality from the age of ten or even less. We hone our skills at what we excel in and neglect our skills in other areas-knowing we can buy such services from others. We find our niche.
Sulloway is saying the same about families. Each individual seeks an empty niche. For eldest children this means the orthodox route, for younger children it means searching more heterodox routes. Differentiation is the goal.
How do Sulloway’s ideas mesh with Freud’s? Sigmund Freud clearly believed that family dynamics were vitally important in determining personality, but he emphasised more the dynamics between parents and offspring than between siblings. He also placed far too much emphasis on the juvenile libido. None the less, stripped of its placebo quackery and self-fulfilling prophecies, psychoanalysis is right to go back to childhood in search of formative influences. Character and temperament are formed in the competition between brothers and sisters to find a suitable niche.
Sulloway stresses that a family is not a single environment. It is a very different environment for a child spending its formative years as the eldest and a child spending its formative years as the youngest. We all know this, as people and especially as siblings, but we seem to forget it when we turn into historians or sociologists. We argue that a person’s class, wealth and forebears make a difference to their personality, but omit their birth order.
Sulloway admits of only one factor that consistently seems to mitigate the effect of birth order: shyness. Shy people show less of the stereotype of their birth rank. Shy elder children lack the confidence and inflexibility of the tribe. Shy younger children lack the rebelliousness and openness of theirs. In Sulloway’s sample of scientists, all shy people were just as likely to support revolutionary ideas, irrespective of their birth order. The reason is that temperament “is drafted into the service of sibling strategies.” Our personalities are formed by a combination of innate temperament and family niche.
At this point, Sulloway is stretching the limits of his method and samples, and risking attack from more orthodox psychologists. The most powerful test of any theory in something as mushy as the science of personality is whether exceptions prove the rule or not. There are plenty of exceptions to Sulloway’s thesis: elder sons who joined revolutions or younger ones who reacted to them. Some of them remain troubling, such as Martin Luther, an elder child. Sulloway’s explanation for Luther is not very convincing: he was in an area favourable to reform and a member of the lower clergy, which generally favoured reform. Likewise, Sulloway excuses first-born Francis Crick and Jim Watson on the grounds that their discovery of the structure of DNA was a “technical breakthrough” rather than a radical revolution. Perhaps, but it sounds like special pleading.
Other exceptions do seem to prove the rule, however. The Archduke Ferdinand of Austria, a leader of the counter-Reformation, was a younger child reared as a first born with a younger sister. He did not meet his elder brother until his teens so he was in effect psychologically an elder child; reactionary authoritarianism came naturally to him. Johannes Kepler, a radical eldest child, had a terrible relationship with his parents and especially his vicious and eventually deserting father. So too did Mao Tse-tung. Conflict with parents, Sulloway argues, breaks the pattern and usually radicalises eldest children.
Exceptions aside, some of the cases that do fit the rule are impressive. Voltaire’s elder brother was pious, priggish and conventional, a striking contrast to Voltaire. Moreover, the effect of birth order can perhaps be cumulative. Darwin was a younger child for four generations in a row. The three most prominent evolutionists of the late 18th century and early 19th century, Jean-Baptiste Lamarck, Erasmus Darwin and Etienne Geoffroy St Hilaire, had 27 elder siblings between them. Benjamin Franklin, 15th of 17 children, was indentured at the age of 12 to a violent brother’s business before running away to Philadelphia. Somehow, don’t you just know that Franklin was a younger child?
If younger-childness is cumulative, then something bizarre seems to happen to eldest children who are radical. They have a habit of turning violent as they marry their radicalism (often, says Sulloway, inherited from later-born parents) to their authoritarianism. It is no surprise to find that Stalin, Mussolini and Carlos the Jackal were first borns. Hitler was his mother’s oldest child, but had two older half-siblings, the youngest six years his senior. From the age of seven, he was the oldest child in the house in a family of three. He was, as a child, an expert in getting his own way.
To test Sulloway’s theory, I went to Debrett’s Distinguished People of Today and looked up six prominent Tories of the 1980s, predicting correctly the birth order of the three I did not know. Mar-garet Thatcher, Norman Tebbit and Nicholas Ridley, radicals to the end, were second children. Douglas Hurd, Ian Gilmour and Geoffrey Howe, conservatives all, were eldest sons. How much of the political revolution of the 1980s do we owe to Miss Muriel Roberts bullying her younger sibling in Grantham in the 1920s? It is an interesting thought, to say the least. Margaret Thatcher was exceptional in one respect. Younger children are generally too rebellious to thrive in politics. American presidents and British prime ministers, such as Franklin Roosevelt and Winston Churchill, have been disproportionately first born.
History is littered with contingency and confounding factors. It would be as absurd to turn Sulloway’s idea into a creed as it demonstrably was to turn Marxist and Freudian ideas into creeds. If it catches on, though, that will probably be its fate and soon there will be legions of Sullowayists, all elder children, inflexibly and dogmatically defending their untarnished hero’s idea as the central and overarching theme of all sociology. Sulloway himself, of course, is a later-born child.
I instinctively like Sulloway’s theory, but then as a third child, I suppose I would. Some people I have discussed it with automatically dismiss it with little thought. I suspect they are mostly first borns. Psychology, unlike physics, is plagued by subjectivity.