In early modern Europe — roughly the period from 1500 to 1789 — scientists didn’t exist. That term wasn’t coined until the 19th century. Instead, those who probed the mysteries of what Douglas Adams famously called “life, the universe and everything” viewed their speculations as either theology or “natural philosophy.” Historically as well as figuratively, Renaissance men (and an occasional woman) regularly dared to take all knowledge for their province.

“A Magical World,” by Derek K. Wilson (Pegasus/Pegasus)

As Derek K. Wilson, a prolific popular historian, reminds us in “A Magical World,” this meant that people didn’t distinguish between what we now call science and superstition. Squint a bit and alchemy is just chemistry; any belief in predestination makes astrology seem almost logical. As Wilson writes, “scientia” was a unity because “all knowledge emanated from and found its consummation in God.” He points out that Isaac Newton, no less, devoted as much time to biblical exegesis, alchemical experiments and other occult matters as he did to theorizing about gravity and working out the principles of calculus. According to one modern scholar, Newton should be viewed as both a great scientist and “the last of the magicians.”

Wilson structures “A Magical World” as essentially a series of lightly sketched biographies of the era’s most prominent theologians, philosophers, physicians, cosmographers and antiquaries. As a result, the book resembles a slimmed-down version of Will and Ariel Durant’s still highly readable, multivolume work of intellectual history, “The Story of Civilization.” Here are two- to six-page portraits of — take a big breath — Francis Bacon, Erasmus, Paracelsus, Martin Luther, John Calvin, Tycho Brahe, Copernicus, Galileo, John Dee, Giordano Bruno, Nostradamus, Ambroise Paré, Descartes, Spinoza, Hobbes, Robert Boyle, Leibnitz, Voltaire, David Hume, Rousseau, John Wesley and a dozen others.

Wilson also examines themes that run through these 300 or so years: For instance, people living in this largely Christian culture most wanted an answer to a single, fundamental question: What must I do to be saved? During the Middle Ages, the answer was straightforward: Obey the teachings and clergy of the Catholic Church. But Luther and Calvin, among others, brought about a Reformation — the word “Protestant” was first used in 1529 — by emphasizing instead the need for “grace and inward faith as opposed to reliance upon rituals and priestly intercession.” To be saved you needed only to believe in Jesus Christ and to read the Scriptures and take them to heart.

This new emphasis on personal faith grounded in the word of God led to intense spiritual self-examination, as well as a flowering of biblical scholarship and translation. Yet superstitious beliefs still flourished. In the 17th century, Wilson stresses, “religion was an amalgam of Christianity and folklore. God and the Devil were invisible realities, as were fairies, goblins, demons and the saints. They manifested themselves through objects — holy relics, charms, herbal remedies and horoscopes — and through people — preachers, witches and magicians. The Reformation had removed some of these things from the spiritual landscape — but not all of them. And it had added other items to the environment — prophecy (especially the apocalyptic sort), personal interpretation of the Bible and divine endorsement of political change.”

Before long, the breakup of a unified Christendom coupled with religious fanaticism — then called “enthusiasm” — led to the genocidal atrocities of the Thirty Years’ War, which between 1618 and 1648 “wiped out 35 per cent of the populations of the combatant nations.” Belief in witchcraft resulted in the burning and hanging of thousands more. Bubonic plague further contributed to a zeitgeist of apocalyptic doom.

Meanwhile, throughout this era people frequently associated great learning with the magus Dr. Faustus, who sold his soul to the Devil for knowledge and power and fleshly pleasure. By the early 18th century, moral instability encouraged both libertinism and chiliasm. As Wilson writes, “While worldlings were living as though there was no tomorrow, fanatical preachers were warning that there was a tomorrow — the day of God’s fearsome judgement.”

In its whirlwind survey, “A Magical World” touches on astronomical discoveries and the development of the microscope, but also on the activities of Thomas Harriot’s occult “School of Night.” Wilson discusses Pascal’s wager, which contends that — given the risks — believing in God is the only sensible bet. We learn that the word “psychology,” meaning the study of the soul, starts its long history in the 17th century and that William Harvey revolutionized medicine with a sentence of consummate simplicity: “The movement of the blood is constantly in a circle and brought about by the beat of the heart.” Even as John Locke argued that the infant mind was a blank slate waiting to be scribbled on by the experiences of the senses, the skeptical philosophy of Pyrrhonism utterly “rejected all certainties and believed that neither religious revelation nor scientific deduction could offer irrefutable knowledge.”

The author Derek K. Wilson (Little Brown U.K./Little Brown U.K. )

Because “A Magical World” aims to be briskly concise, it does risk coming across as facile and cursory. Inexplicably, Wilson quotes from seemingly haphazard editions — online sources, an abridged version of Boswell’s “Life of Johnson,” and even “The Great Books of the Western World” (getting the volume number for Hobbes wrong). At one point he identifies Voltaire’s “Candide” as a play (instead of a short novel) and mistakenly writes Charles, instead of John, Maynard Keynes. The work of several of our leading contemporary scholars of this period, most notably Anthony Grafton, Ingrid D. Rowland and Steven Nadler, goes unmentioned.

So while “A Magical World” testifies to Wilson’s intellectual energy, it simultaneously reveals a certain breezy amateurism. Nonetheless, it certainly remains worth reading if only to be reminded that zealotry and dogmatism are despicable and that few things are more important than free inquiry and the questioning of authority.

Michael Dirda reviews books each Thursday for The Washington Post.

a magical world
Superstition and Science from the Renaissance to the Enlightenment

By Derek K. Wilson

Pegasus. 304 pp. $27.95