In March, 1668, Adriaan Koerbagh, a Dutch physician in his mid-thirties, hired Johannes Van Eede, a printer in Utrecht, to publish his new book, “A Light Shining in Dark Places, to Shed Light on Matters of Theology and Religion.” But Van Eede, after setting the first half of the manuscript, became uneasy about its highly unorthodox contents. Koerbagh argued that God is not a Trinity, as the Dutch Reformed Church taught, but an infinite and eternal substance that includes everything in existence. In his view, Jesus was just a human being, the Bible is not Holy Writ, and good and evil are merely terms we use for what benefits or harms us. The only reason people believe in the doctrine of Christianity, Koerbagh wrote, is that religious authorities “forbid people to investigate and order them to believe everything they say without examination, and they try to murder (if they do not escape) those who question things and thus arrive at knowledge and truth, as has happened many thousands of times.”
Now it was about to happen to Koerbagh himself. Van Eede, either outraged because of his religious beliefs or worried about his own legal liability, stopped work and turned over the manuscript to the sheriff of Utrecht, who in turn informed the sheriff of Amsterdam. Koerbagh was already well known to the authorities there; in February, they had seized all copies of his previous book, “A Flower Garden of All Sorts of Delights,” in which he had denied the existence of miracles and divine revelation. Realizing that he was in danger, Koerbagh went on the run, ending up in Leiden, where he disguised himself with a black wig. But a reward was offered and in July someone turned him in. Koerbagh was interrogated, tried, and sentenced to ten years in prison for blasphemy, to be followed by ten years of exile. The long sentence turned out to be unnecessary: he lasted just a year in prison before dying, in October, 1669.
A few months later, an even more subversive book was published in Amsterdam: “Tractatus Theologico-Politicus,” an anonymous Latin treatise that declared the best policy in religious matters to be “allowing every man to think what he likes, and say what he thinks.” In the preface, the author gave thanks for the “rare happiness of living in a republic, where everyone’s judgment is free and unshackled, where each may worship God as his conscience dictates, and where freedom is esteemed before all things dear and precious.” But the fact that the author withheld his name, and that the book’s Amsterdam publisher claimed on the title page that it had been printed in Hamburg, told another story. The author and the publisher were well aware that their unshackled judgment could put them in shackles.
These feints couldn’t stop readers, or the authorities, from quickly figuring out that the “Tractatus” was the work of Baruch Spinoza. Although Spinoza, then in his late thirties, had previously published only one book, a guide to the fashionable philosophy of René Descartes, he was one of Amsterdam’s most notorious freethinkers. As a young man, he had been expelled from the city’s Jewish community for his heretical views on God and the Bible. (He published under the name Benedictus de Spinoza, Benedictus being the Latin equivalent of Baruch, which means “blessed” in Hebrew.) Living a quiet, solitary existence, supporting himself by grinding lenses for microscopes and telescopes, Spinoza developed his ideas into a comprehensive philosophical system, which he shared with a circle of friends in letters and conversations. When Koerbagh was interrogated, he was asked whether he had fallen under Spinoza’s malign influence. He acknowledged that they were friends, but insisted that they had never discussed ideas—even though what he wrote about God closely resembled what Spinoza had been saying for years.
Ministers in several cities immediately forbade booksellers to carry the “Tractatus,” and, in 1674, it was officially banned in the Netherlands, along with Thomas Hobbes’s “Leviathan.” Under the circumstances, Spinoza’s praise of Dutch freedom might well sound sarcastic. But the truth is that, compared with most of Europe in the seventeenth century, the Netherlands really was a haven of tolerance. In Spain or Italy, a book like Spinoza’s could get its author burned by the Inquisition; as it was, the attacks were aimed at his ideas, not his life. His praise of his country is better seen as a kind of appeal: Perhaps no country in Europe was truly free, but the Netherlands might be if it tried.
For Ian Buruma, a writer and historian and a former editor of The New York Review of Books, it is Spinoza’s dedication to freedom of thought—what he called libertas philosophandi—that makes him a thinker for our moment. In his new book, “Spinoza: Freedom’s Messiah,” a short biography in Yale University Press’s Jewish Lives series, Buruma observes that “intellectual freedom has once again become an important issue, even in countries, such as the United States, that pride themselves on being uniquely free.”
No American has to fear Adriaan Koerbagh’s fate, no matter how unpopular his or her opinions. Still, Buruma argues, “liberal thinking is being challenged from many sides where ideologies are increasingly entrenched, by bigoted reactionaries as well as by progressives who believe there can be no deviation from their chosen paths to justice.” And it is certainly true that, in the age of social media, informal pressure to toe a certain line can be as effective as legal threats. Offending the wrong people, even for a moment, can blow up the career of anyone from a Y.A. novelist to an Ivy League president.
In calling Spinoza a “messiah,” Buruma follows Heinrich Heine, the nineteenth-century German Jewish poet, who compared the philosopher to “his divine cousin, Jesus Christ. Like him, he suffered for his teachings. Like him, he wore the crown of thorns.” According to Jonathan Israel, a historian whose encyclopedic biography “Spinoza, Life and Legend” came out last year, “No other personage of his era came even close to being so decried, denounced and condemned in weighty texts of exhaustive length, over so long a span of time, in Latin, Dutch, French, English, German, Spanish, Portuguese, Hebrew, and other languages.”
Like deconstruction or critical race theory, “Spinozism” became a popular target for many a moralist who could not have said exactly what it meant. Yet, although Spinoza was certainly a champion of political and intellectual freedom, he had no interest in being a martyr for them, and, if his life teaches anything about thinking in dangerous times, it is how prudence and boldness can go hand in hand. Not for nothing did he wear a ring inscribed with the Latin word “Caute”: “Be cautious.”
The boldest act of defiance in Spinoza’s life came at the beginning of his career as a philosopher, and made that career possible. In July, 1656, when he was twenty-three years old, Spinoza was cast out of Amsterdam’s Jewish community in a public ceremony. There are few contemporary sources for Spinoza’s early life, and it’s not known precisely what led to this rupture.
But the text of the ban, or herem, read aloud at a synagogue on Amsterdam’s Houtgracht canal, has been preserved, and it makes clear that what the community objected to was not any personal misdeed but Spinoza’s “evil opinions” and “abominable heresies,” which he refused to recant under pressure. For this reason, the leaders of the congregation declared, Spinoza “should be excommunicated and expelled from the people of Israel.” They invoked the fearsome punishment for disobedience laid down by Moses in the Book of Deuteronomy: “Cursed be he by day and cursed be he by night; cursed be he when he lies down and cursed be he when he rises up. Cursed be he when he goes out and cursed be he when he comes in.”
Spinoza wasn’t present to hear this curse read aloud, but he couldn’t escape its effects. The Jewish community into which he was born, in 1632, was uniquely close-knit, set off not only from the Dutch Christians around it but from other Jewish communities in Western Europe. Amsterdam’s Jews were descended from Portuguese conversos, Jews forcibly converted to Catholicism at the end of the fifteenth century, who continued to practice their faith in secret for generations. Spinoza’s parents and grandparents were among the many Portuguese Jews who moved to the Netherlands in the early seventeenth century, drawn by the promise of religious tolerance as well as commercial opportunities. Buruma, Dutch-born and Jewish on his mother’s side, notes that Spinoza and his brother were the first members of their family “in many generations to be born as a Jew, and not a crypto-Jew.”
Buruma writes that Spinoza’s excommunication was like being “ ‘canceled,’ as people might now say,” but this was a retribution that a Twitter mob could only dream of. Under the terms of the herem, all Jews, including Spinoza’s relatives, were forbidden to talk to or even go near him. He could no longer hope to live among the people he had known all his life, to do business with them, or to get married and start a family. The fact that Spinoza was willing to sacrifice everything for his right to think and speak freely shows how seriously he took libertas philosophandi, before he had published a word of philosophy.
Spinoza’s apostasy also makes him a key figure in modern Jewish history. He was hardly the first Jew to abandon Judaism, but he might have been the first to do so publicly without becoming a Christian or a Muslim. Instead, he fashioned a secular life, something that was hardly conceivable before the seventeenth century. In the “Tractatus,” he argued that, in a commercial state like the Netherlands, traditional religious identities no longer had any real meaning, anyway: “Matters have long since come to such a pass, that one can only pronounce a man Christian, Turk, Jew, or Heathen, by his general appearance and attire, by his frequenting this or that place of worship, or employing the phraseology of a particular sect—as for manner of life, it is in all cases the same.”
For members of later generations of European Jews hoping to emancipate themselves from religion, such as Heine and Sigmund Freud, this independence made Spinoza a role model. As Buruma writes, “He chose to think freely, and that made his tribal membership impossible.” Instead, Spinoza assembled his own tribe of like-minded individuals, most of them freethinking liberal Protestants. Israel and another eminent Spinoza biographer, Steven Nadler, have shed light on these key relationships. Franciscus van den Enden, Spinoza’s Latin teacher and sometime landlord, was a former Jesuit who drew up a plan for a utopian society in New Netherland, the Dutch colony that became New York; he ended up being hanged by the French for helping to hatch a plot against Louis XIV. Lodewijk Meyer, a leading figure in Dutch literary life, is believed to be the author of an anonymous book, published in 1666, that caused a huge scandal by arguing that the Bible should be analyzed critically and scientifically. Johannes Bouwmeester co-founded a club for freethinkers with the defiant name Nil Volentibus Arduum (“Nothing Is Difficult for the Willing”).