In the 1980s, social scientist James Flynn made a startling discovery: Real IQ scores had been going up, on average, three points every decade since the early 20th century. The existence of this increase had been masked by the fact that the test gets updated and renormed every generation or so, pushing the average score back to 100.
The implications of the eponymous "Flynn effect" are astonishing. A person of average intelligence today would have registered a full two standard deviations higher a century ago, giving him a "very superior" score of 130. We're getting smarter. A lot smarter.
The cause of the Flynn effect is still the subject of debate, but it's not just that we're getting better at taking tests. If that were the case, intelligence scores throughout the test's subcategories should have improved across the board. But results in areas such as information, arithmetic, and vocabulary have nudged only slightly upward over the past half-century when test taking became ubiquitous. Instead, the increases have occurred almost exclusively in the two subtests that most require abstract reasoning (and are least sensitive to education and practice): similarities and matrices.
The section called similarities asks questions such as "What do dogs and rabbits have in common?" If you answer, "Both are mammals," says Flynn, you are thinking like a scientist in classifying organisms by type-an abstraction. If you said, "You use dogs to hunt rabbits," you are thinking concretely, imagining a tangible use for a dog. Matrices are abstract figures that require determining a pattern and then deducing the missing piece, as in the example below.
The improved performance in these two areas (and not the others) suggests that an explanation may be found in broader social changes in society that have led to more abstract reasoning. Instead of manipulating plows, cows, and machinery as almost everyone did in the 19th century, many more of us are now manipulating words, numbers, and symbols. Our economy shifted from agriculture and industry to information, demanding more conceptual, abstract thinking at every level of life.
Flynn himself attributes the effect to an accelerating capacity for people to view the world through "scientific spectacles." During a Skeptic magazine interview, he recalled research by the psychologist Alexander Luria on the reasoning abilities of Russian peasants a century before: "The illiterate Russian peasants Luria studied were not willing to take the hypothetical seriously. He said, 'Imagine that bears come from where there is always snow and imagine that if bears come from where there is always snow they are white. What color would the bears be at the North Pole?' and they would respond something like, 'I've only seen brown bears. If an old man came from the North Pole and told me I might believe him.' They were not interested in the hypothetical, or abstract categories. They were grounded in concrete reality. 'There are no camels in Germany. B is in Germany. Are there camels there?' They said, 'Well, it's big enough, there ought to be camels. Or maybe it's too small to have camels.'"
Flynn and his colleague William Dickens suggest that the increases in reasoning abilities may have started centuries ago with the industrial revolution, which required certain cognitive abilities not needed in a predominantly agricultural society. The manipulation of composite machinery, coupled to the migration to cities with their more complex and cosmopolitan cultures, may have launched the effect. But, Flynn says, it really took off after 1950, when "IQ gains show a new and peculiar pattern. They are missing or small on the kind of IQ tests closest to school-taught material like reading and arithmetic. They are huge on tests that emphasize on-the-spot problem-solving, like seeing what verbal abstractions have in common, or finding the missing piece of a Matrices pattern, or making a pattern out of blocks, or arranging pictures to tell a story. Perhaps the industrial revolution stopped demanding progress in the basics and started demanding that people take abstract problem-solving more seriously." That makes sense. In 1900, Flynn says, only 3 percent of Americans had cognitively demanding jobs-professional occupations in management, medicine, the law, and the like. That figure climbed to 35 percent by 2000 and continues ever upward.
Our improved ability to reason abstractly may also be the result of the spread of scientific thinking-reason, rationality, empiricism, skepticism. Thinking like a scientist means employing all our faculties to overcome our emotional, subjective, and instinctual brains to better understand the true nature of not only the physical and biological worlds, but the social world (politics and economics) and the moral world (abstracting how other people should be treated) as well.
The Moral Flynn Effect
Since the Enlightenment, humans have demonstrated dramatic moral progress. Almost everyone in the Western world today enjoys rights to life, liberty, property, marriage, reproduction, voting, speech, worship, assembly, protest, autonomy, and the pursuit of happiness. Liberal democracies are now the dominant form of governance, systematically replacing the autocracies and theocracies of centuries past. Slavery and torture are outlawed everywhere in the world (even if occasionally still practiced). The death penalty is on death row and will likely go extinct sometime in the 2020s. Violence and crime are at historic lows, and we have expanded the moral sphere to include more people as members of the human community deserving of rights and respect. Even some animals are now being considered as sentient beings worthy of moral consideration.
Abstract reasoning and scientific thinking are the crucial cognitive skills at the foundation of all morality. Consider the mental rotation required to implement the Golden Rule: Do unto others as you would have them do unto you. This requires you to change positions-to become the other person-and then to extrapolate what action X would feel like as the receiver instead of the doer (or as the victim instead of the perpetrator). Although the Golden Rule has been around for thousands of years, as evidenced in the Old Testament, with its tales of genocide, infanticide, rape, and pillaging of peoples in other tribes, it was practiced in a very limited fashion compared to today.
Today, the moral arc of the universe may be bending in the right direction, in part because of something like a "moral Flynn effect," a term coined by the psychologist Steven Pinker in The Better Angels of Our Nature. Pinker said "the idea is not crazy," but I would go further. I believe that our improvement in abstract reasoning generally has translated into a specific improvement in abstract moral reasoning, particularly about other people who are not our immediate kith and kin.
Evolution endowed us with a natural tendency to be kind to our genetic relations but to be xenophobic, suspicious, and aggressive toward people in other tribes. As our brains become better equipped to reason abstractly in such tasks as lumping dogs and rabbits together into the category "mammal," so too have we improved in our capacity to lump blacks and whites, men and women, straights and gays into the category "human."
As Enlightenment philosophers and scholars consciously adopted the methods of science to establish such abstract concepts as rights, liberty, and justice, successive generations have become schooled in thinking of these abstractions as applied to others in matrices-like mental rotations.
The Evidence
Social scientists have gathered considerable evidence on the connection between various types of intelligence and moral values and behavior. Numerous studies from the 1980s onward, for example, find that intelligence and education are negatively correlated with violent crime. As intelligence and education increase, violence decreases, even when controlled for socioeconomic class, age, sex, and race.
Even more intriguing is newer evidence that shows a positive correlation between literacy and moral reasoning, most particularly between reading fiction and being able to take the perspective of others. Perspective-taking in novels requires a matrices-like rotation of relational positions combined with an understanding of what it would feel like if X happened to you, even though the "you" in this case is a character in the novel.
In a 2011 study, for example, the Princeton neuroscientist Uri Hasson and his team scanned the brain of a woman while she told a story out loud that the scientists recorded and subsequently played back for other subjects while their brains were being scanned. When the reader's emotional brain region called the insula lit up during a certain portion of the story, so too did the listeners' insulas; when the woman's frontal cortex became active during a different part of the story, the same region in listeners' brains was also activated. It's almost as if the fictional story synchronized the reader's and listeners' brains.
A 2013 study by the psychologists David Comer Kidd and Emanuele Castano explored the causal relationship between reading high-quality literary fiction and the ability to take the perspective of others, as measured by one of several well-tested tools, such as judging others' emotions and eye-gaze directionality for interpreting what someone is thinking. The researchers found that participants who were assigned to read literary fiction performed significantly better on these "mind reading" tests that measured where subjects were looking and how they judged the emotions of others than did participants assigned to the other experimental groups, which did not differ from one another.
This experiment is important because it nails down the direction of the causal arrow from reading literary fiction to perspective taking, eliminating the objection that perhaps people who are interested in and good at interpreting the mental states of others just happen to be people who read novels.
In terms of justice and reason, in a 2004 paper aptly titled "Less Thought, More Punishment," the psychologist Michael Sargent found a correlation between a high "need for cognition" (enjoying mental challenges such as those employed in intelligence tests) and low demand for punitive justice, even when such attitudes are controlled for age, sex, race, education, income, and political orientation. The Enlightenment principle that punishments should be tailored to fit the crime requires grasping the abstract concept of proportionality, a process fundamental to all scientific thought.
Intelligence also predicts classical liberal attitudes toward helping others. A 2010 analysis of data from the National Longitudinal Study of Adolescent Health found that among 20,000 young adults there was a positive correlation between IQ and liberalism. Data from the General Social Survey clarified the link in noting that the correlation involves classical liberalism of the Enlightenment kind, in which smarter people were less likely to agree that the government should redistribute income from the rich to the poor but more likely to agree that the government should help African Americans to compensate for historical discrimination. In other words, the effect was more about the moral dimension of how people are ethically treated instead of the more concrete dimension of economic adjustment.
The psychologist Ian Deary and his colleagues confirmed this link in a 2008 paper published in Psychological Science titled "Bright Children Become Enlightened Adults." Deary et al. found a positive correlation between the IQ of British children at the age of 10 and their endorsement of anti-racist, socially liberal, and pro-working women attitudes at the age of 30, holding the usual potentially intervening variables constant. By "enlightened," Deary meant the values that came directly from the Enlightenment, the definition for which he adopted from the Concise Oxford Dictionary: "a philosophy emphasizing reason and individualism rather than tradition."
Intelligence predicts economic attitudes, most notably abstract concepts such as the way that free trade is a positive-sum game. This runs counter to our folk-economic intuitions that most economic exchanges are zero-sum in a fixed pie of wealth. The economists Bryan Caplan and Stephen Miller culled data from the General Social Survey and published an article in a 2010 issue of the journal Intelligence tellingly titled "Intelligence Makes People Think Like Economists." They found a correlation between intelligence and openness to immigration, free markets, and free trade, and a reluctance to endorse government make- work projects, protectionist policies, and business interventionism.
Concrete thinking leads us to endorse economic tribalism along with populist and nationalist zero-sum attitudes toward other tribes (nations, in the modern world). Abstract reasoning leads us to consider members of other tribes (nations) as potential trading partners to be respected rather than as potential enemies to be conquered or killed.
Democratic tendencies, most notably the rule of law, can also be predicted by intelligence. The German psychologist Heiner Rindermann ran correlational studies on a number of data sets from many different countries, examining their average scores on popular intelligence tests and measures of academic achievement from the period 1960 to 1972. Rindermann found that intelligence scores predicted the level of prosperity, democracy, and rule of law found in those countries in the subsequent period 1991 to 2003-even when controlling for the country's prior level of prosperity. In other words, all other things being equal, a country whose citizens are better able to reason abstractly will be a more prosperous and moral country.
Moral Morons No More
If the moral Flynn effect is real-and I think it is-the implications for the future of humanity are encouraging as we continue expanding the moral sphere along with the abstract complexity of our technologies and culture.
It's hard to accept the notion that people in the early 20th century were moral idiots, two standard deviations dumber than us. Their attitudes about race and gender sure seem morally moronic to us today, but does that mean in another half century our descendants will look at us with equal moral dumbfoundedness? Surely we've learned some things that will carry civilization forward and that are grounded in relatively permanent principles, such as equal rights for everyone. I believe we have.
Given that the moral Flynn effect is cultural, not evolutionary, there are no biological constraints on what we are capable of becoming in centuries and millennia hence, if we apply what we know works to expand the moral sphere: liberal democracy and universal franchise, free trade and market capitalism, property rights, civil rights, equal treatment under the law, porous political and economic borders and the freedom to travel, and other characteristics of free societies that have been hard-learned and earned over the centuries. As we're witnessing today the unfolding of a new rights revolution for gays and lesbians, and yet another for animals, there is no reason to limit our thinking of how much better life can be for more people in more places: Freedom and abundance for all is within our reach this century. We can bend that moral arc even more.
Michael Shermer (mshermer@skeptic.com) is the publisher of Skeptic magazine and monthly columnist for Scientific American. This essay is adapted from his new book, The Moral Arc: How Science and Reason Lead Humanity Toward Truth, Justice, and Freedom, published by Henry Holt.
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