Siep Stuurman, a Dutch intellectual historian, won’t be familiar to most American readers. Before The Invention of Humanity, his only book published in English was a biography—and a celebration—of another little-known author, the French Cartesian philosopher François Poullain de la Barre, who wrote three treatises on the equality of the sexes in the 1670s. “The mind has no sex whatsoever,” Poullain declared, and he told his female readers: “You are endowed with reason; use it, and do not sacrifice it blindly to anyone.” These treatises, Stuurman argues, played a significant part in “the invention of modern equality.” His new book is a much larger and bolder account of that “invention,” stretching across two millennia and virtually every known civilization; it takes as its focus not just the idea of equality but also of our “common humanity.” 

Stuurman’s earliest (untranslated) books were about Dutch socialism, and he is obviously a supporter of both of these ideas. So, he argues, is everyone else these days, though the support is often inconsistent and hypocritical. Once, long ago, the ideas of equality and a common humanity were literally “unthinkable”; today, they are the default position of almost all of us. The Invention of Humanity is the story of how this dramatic change came about—and how long it took. 

Stuurman’s book is a big one, and it violates many of the current rules of academic writing—especially the ones regarding turf. Stuurman provides us with a critical discussion of texts and authors from ancient Israel, Greece, and China; early Christendom and Islam; medieval Europe and Central Asia; Europe’s colonizers and the colonized peoples; the Enlightenment and the American, French, and Haitian revolutions; the Indian and African national-liberation movements and the African-American struggle for equality. The book ends with an account of the drafting of the 1948 Universal Declaration of Human Rights following a critique of Samuel Huntington’s the “clash of civilizations.” 

Stuurman includes a good number of philosophers and religious writers (Confucius, Ibn Khaldun, Francisco de Vitoria, John Locke, and many more) and also the sort of people we now call public intellectuals (Voltaire, W.E.B. Du Bois). Unexpectedly, he also writes about travelers and ethnographers. Covering such a wide terrain and such a long period of time means that he tres­passes on many academic fields, and I am sure the book will be criticized by scholars defending their specific expertise. Don’t let that bother you; Stuurman offers very skillful readings of the texts and figures that he surveys.

The range of his work also requires him to reject the current commitment of many intellectual historians to deep contextualism. These days, scholars are supposed to tell us in great detail how a particular book was read in its time: What did the words mean to their first readers? What other, perhaps lesser-known books and pamphlets were written around the same time? What were the immediate occasions of this writing? Who were the living targets of its arguments? Too much of this sort of thing, Stuurman argues, makes it impossible to understand the lasting significance of a given text. He is, instead, interested in a different question: Why is a text still important to us? And so he provides a more limited context—and then focuses on the temporal placement of each book alongside the others in his universal history. 

Given where the book begins and ends—with equality at first unthinkable and then a commonly accepted thought—I am inclined to call Stuurman’s account a story of progress, a “Whig history.” He’s reluctant to accept this description, and, in fact, some of the earliest assertions of human equality are as good as they get, and some of the latest are radically compromised. The book certainly doesn’t claim that humanity itself has advanced over the centuries, morally or politically. Stuurman’s argument is that the idea of humanity is probably more fully developed and more widely accepted today than it has ever been. This is not to say that we have reached the end of the story, for new versions of inequality have been invented in every age, including our own.

One of the most original features of Stuurman’s book is his account of “the anthropological turn,” which isn’t a single turn in time but a recurrent turning of travelers and ethnographers toward the outside and the “other.” Stuurman begins with the Greek historian Herodotus and the much less well-known Sima Qian, who lived in China three centuries after Herodotus and wrote about the Han empire and the surrounding lands. Both Herodotus and Sima Qian traveled widely, crossing the political and cultural frontiers that separated Greeks and Chinese from the people they called “barbarians.” And both suggested that the separation wasn’t as great as their compatriots thought. Again and again, the anthropological turn has produced reports similar to theirs: The natives of this or that foreign country, for all their strange customs and beliefs, are remarkably like us. Here, according to Stuurman, is a critical moment in the “invention” of humanity.

But one wonders whether what he is describing isn’t more a matter of discovery than invention. When Herodotus writes that the Egyptians call people who don’t speak their language “barbarians,” exactly as the Greeks do, is this an act of inventing or discovering humanity? Herodotus’s aim is to unsettle his Greek readers and force them to recognize their fellowship with the Egyptians. Similarly, when Sima Qian visits the nomads who live north of the Great Wall and reports that their way of life is remarkably and intelligently well-adapted to their environment, this is again a discovery meant to challenge the complacent self-regard of his fellow Chinese: They are not alone in their human ingenuity. Nothing like invention is going on here.

Perhaps the most engaging, and also the most disturbing, of the travelers and ethnographers in Stuurman’s account are the Dominican and Franciscan priests or friars who went to Central America in the wake of the Spanish conquest. Writers like Bartolemé de las Casas and Bernardino de Sahagún described the high civilization of the indigenous peoples (another discovery), and Las Casas conducted a years-long campaign against the greed and brutality of the Spanish colonizers. With Sahagún’s help, a number of Aztec writers “drafted an account of the siege and destruction of the magnificent city of Tenochtitlán by Cortez.” So the colonized were given a voice—though Sahagún later wrote his own account, presenting the conquest as “providential.” Las Casas and Sahagún were hardly in full possession of the ideas of humanity and equality. But they portrayed the Spaniards as far less civilized than these indigenous peoples—and so they took a stand against the prevailing Spanish belief in their own racial and cultural superiority. 

The anthropological turn continues with modern academic anthropology. Stuurman writes about the critique of “scientific racism” by Franz Boas and Ashley Montagu, both of whom would certainly deny that their defense of human equality was an invention; they meant to tell it like it is. But when it comes to the big philosophical and theological systems within which the ideas of humanity and equality have sometimes been defended, Stuurman is correct: These are indeed designed and constructed. Here we can see a long series of historical inventions of our shared humanity—Stoicism, Catholic natural law, Kantian idealism. Consider one of the earliest examples: From a secular standpoint, the God of biblical theology, in whose image all human beings are created, is an invention. The common image, however, is discovered again and again—by Las Casas, for example, and centuries later by Boas. 

Discovery stands alongside invention and is probably more important. This is my only serious disagreement with Stuurman, and it’s mostly a disagreement with the title of his book. He really isn’t, and we shouldn’t be, the prisoners of postmodern “social construction.” Common humanity is a fact, even if, after several millennia of debate, we are still defending its factuality against multiple denials. It’s not fake news; we didn’t make it up. 

Human inequality is commonly described by its defenders as a discovery, but we can allow ourselves to think that it, indeed, is socially constructed. Many different kinds of inequality appear in human history, and each one must be overcome if humanity and equality are to triumph in the practical as well as the ideological world. We have to deal with geographic inequality (the barbarians on the other side of the border), racial inequality (whites or Chinese and the inferior “others”), hierarchical inequality (masters and slaves, aristocrats and commoners), and economic inequality (the rich, the poor, and the desperately poor). These four inequalities are very old and ever-renewed; we know them well. Stuurman adds a fifth to this list, which he thinks is peculiarly modern: temporal inequality. “We” are advanced, and “they” are backward.

This is a modern version of inequality because it implies an acceptance, at least theoretical, of a future egalitarianism. Think of the “civilizing mission” of the modern imperial powers: The idea suggests that all human beings are capable of becoming civilized. It’s just that we are already there, and they have a long way to go—and need our guidance on the difficult journey. The theory of “modernization” is another example of temporal inequality: We are already modern; they have fallen far behind. The others definitely can catch up; the inequality isn’t permanent, though we are likely to insist for a long time that they are not yet where they should be.

There is, unhappily, a left-wing version of temporal inequality, which played a major part in leftist history throughout the 20th century—and still figures, I think, in the 21st. Vanguard theory is an argument not only that some of us are or should be leading the forward march, but also that some of us are more advanced than the rest of humanity in our knowledge of history and society. We have the correct ideological position, and they do not. Therefore, the vanguard’s historical task is to educate, even more than to lead, the others. But sometimes victory precedes education, and then the victorious vanguard is likely to produce a brutally authoritarian regime—required, so the vanguardists in power say, by the “false consciousness” of the masses. This, too, is a version of inequality that needs to be overcome. 

The longest chapter in Stuurman’s book deals with the Enlightenment, which stretches in his account from Descartes (and Poullain de la Barre) to Condorcet—­roughly a century and a half. This is Stuurman’s own field of expertise, and he treats the Enlightenment as a major turning point in human history. Still, the story he tells is nicely balanced: celebratory but also qualified (temporal inequality is invented in these years, though there were hints of it earlier on). He gives the revolutionary Declaration of the Rights of Man (1789) the recognition it deserves, while acknowledging contemporary disagreements about the rights of Jews, blacks, and women.

The Enlightenment doesn’t only mark an advance in the long march of humanity and equality; it also leads to a significant change in the tempo of the march. There is a speedup, which many people have noted when writing about the pace of everyday life in the modern age. But the speedup with regard to humanity and equality is quite specific: It is a political acceleration. Until the 18th century, there were many writers asserting our common humanity and many others denying it—and some, as Stuurman notes, doing both at once. But then something changes. Beginning with the American and French revolutions and developing in the early and mid-1800s, social and political movements committed to egalitarianism suddenly appear in Western Europe and the United States—“suddenly” given the scope of Stuurman’s two-millennia history. Now movements that call themselves “internationalist” aim to draw all humanity into the struggle for equality. This is something radically new, and with it comes the idea that theories about humanity and equality must lead to a practice of humanity and equality—to a radical politics. Abolitionism, the labor movement, feminism in its several waves, the civil-rights movement, and the gay-rights movement all have their origin in this moment when political action became, for people like us, obligatory.

Because The Invention of Humanity is an intellectual history and not a social or political one, Stuurman doesn’t discuss all of these movements. He lets the antislavery movement stand in for the rest, and this is entirely legitimate. But there’s an intellectual invention (I think that’s the right word) that he might usefully have noticed. It was the product of leftist militancy and is what militants call the “unity of theory and practice.” This new unity was critical to the development of the Western left, and it remains so today. The commitment to practice was the source of much of the left’s gains in the 19th and 20th centuries; it is what makes the movements move. The left has had its share of failures and disasters, some of them connected to its belief in temporal inequality and vanguardism. Still, it’s an important part of Stuurman’s story; he could have written more about it. 

But the left is only a part of the story, as this splendid book makes clear. At times one might fault The Invention of Humanity for its survey-like quality, moving from one author and text to another. But Stuurman’s panoramic vision of discovery and invention, reiterated in many different cultural and religious idioms across a vast expanse of time and space, makes for a dramatically original history. Those of us who grew up on the Western left may think that it’s our egalitarian ideology that has been emulated around the world. Not so: The discovery and invention of humanity has been the work of humankind.