How were the Jews different from every other ancient people? Thomas Cahill believes he has the answer, and readers of his previous book, How the Irish Saved Civilization, will not be surprised to learn that it’s sweeping: “We can hardly get up in the morning or cross the street without being Jewish,” he concludes. “We dream Jewish dreams and hope Jewish hopes. Most of our best words, in fact—new, adventure, surprise; unique, individual, person, vocation; time, history, future; freedom, progress, spirit; faith, hope, justice—are the gifts of Jews.”

Faced with this near-messianic claim, a one-word response suggests itself. It’s a word, fittingly, that is barely in Cahill’s vocabulary: maybe.

Cahill caused a modest sensation with How the Irish Saved Civilization, which argued that a few Hibernian monks preserved the Christian and classical heritages while the rest of Europe went on a Dark Ages bender. The author apparently liked the reaction, because that book is now identified as the first in a seven-volume series dubbed “The Hinges of History.” (That’s the official title, but the marketing guys might call it “Short, Flattering Books About People Whose Descendants Have Significant Disposable Income.”) The Gifts of the Jews: How a Tribe of Desert Nomads Changed the Way Everyone Thinks and Feels is the second in this newly identified series.

Cahill has a background in religious publishing, but lately he has burnished his academic credentials; his latest bio identifies him as a 1996-97 visiting scholar at the Jewish Theological Seminary of America. Still, he’s a resolute popularizer. The narrative of his new book transpires entirely in the era he declines to call B.C.E.—the Christian-centric B.C. is good enough for him—but he describes traveling backward in time “like characters in a Steven Spielberg film,” suggests of Abraham and his family that “we can almost X-ray their mental baggage,” refers to a Hebrew king’s advisers as “buds,” notes that the Old Testament God “is obviously not a member of any known 12-step program,” compares the story of Sodom and Gomorrah to The Night of Living Dead, and describes King David as “the captain of the football team [and] the supersalesman.”

Comparing Biblical heroes to capitalist champions is a standard (and annoying) practice of American Christian fundamentalists, who might approve of Cahill’s reference to Moses’ need for “a middle management team.” The author is not a fundamentalist, however. He takes some pleasure in purveying the deflating interpretations of contemporary Biblical scholars: The parting of the Red Sea was actually a successful passage through a swamp at low tide, for example, and the manna that sustained the Israelites in the desert “was probably white edible insect secretions to be found on the branches of some rare Sinai plants.”

Cahill is enough of a liberal to deplore—and not try too hard to rationalize—the Israelites’ genocidal campaign to conquer Canaan and to reject as “painfully embarrassing” the Christian belief that its religion superseded Judaism. Although he rejects feminist arguments that the earliest deities were female, he extols the rare Old Testament instances in which women emerge as fully human. Even more daringly, he likes to gossip about ancient sexual practices, doubting that in his later years Abraham could “get it up” and offering an account of a Sumerian temple orgy that’s lurid enough for an Anne Rice novel (and is, he admits, equally fictional).

Such informality is intended to put the casual reader at ease, but there is much in The Gifts of the Jews that doesn’t go down easy. Cahill treads brazenly through the mists of prehistory, asserting that the Israelites are responsible for “the only new idea that human beings have ever had.” This is the notion that life is progressive rather than cyclical, which the author contends is the source of Western civilization’s concepts of history, progress, individuality, and justice. Everyone else, he suggests in a quick dismissal of Indian, Chinese, Mayan, and pre-Socratic Greek culture, was just chasing his own tail.

Cahill can’t prove he’s right, but he’s in conveniently uncharted territory; the Old Testament era’s chronology is vague, and its contemporaneous sources are scant. That’s one reason the book’s assurances are suspect; another is Cahill’s willingness to rely on “common sense” that disregards scholarly doubts: Writing about the Sumerian treatment of venereal disease, he notes that it was “called ‘a disease of the tun and nu’—and though the experts tell us they can not be sure of the meaning of these two words, the layman will have little trouble identifying them.”

In the realm of Biblical scholarship, I’m certainly a layman, but that doesn’t mean I have to accept this winking appeal to my lax judgment. Perhaps experts have good reason not to jump to Cahill’s conclusions. Despite its unblinking certainty, The Gifts of the Jews does not establish that the Israelites invented monotheism, justice, or individualism. After all, the Egyptian pharaoh Akhnaten may have been the first to declare the existence of only one god, and many of the features of modern Western religion seem to come not from ancient Judaism but from Zoroastrianism. (Cahill mentions Akhnaten in passing but ignores Zoroastrianism altogether.) There’s no major world religion that doesn’t advocate justice, and for individualism we can probably continue to credit the Greeks.

He has already celebrated the Irish, so Cahill obviously likes underdogs. He has similar sympathies for the Israelites, and identifies them affectionately as “a ragbag of runaway slaves.” But some contemporary scholars think the influence of the early Semites has been historically underestimated and argue that they were wealthier and more powerful than was once believed. Some scholars also now suggest that the Israelites didn’t become true monotheists until after the Assyrians and Babylonians conquered Israel’s two kingdoms in the eighth and sixth centuries B.C.E. (well after the philosophical breakthrough that Cahill attributes to Moses’ receiving the Ten Commandments).

Since this book is intended for a general audience, it contains no footnotes. Instead, Cahill provides an appendix with a few paragraphs about his sources for each chapter. Here he admits to “simplification[s] that I believe do no harm” and to “simpli[fying] complex questions so that my line of argument may appear clearly.” He acknowledges some of the questions that will have occurred to skeptical readers and, remarkably, writes that “to say—unequivocally—that monotheism and individual destiny began with Avraham [Abraham] or that Moshe [Moses] is responsible for new notions of time and moral behavior is more than I mean to affirm.”

Considering that this is exactly what the book affirms, such a caveat is bizarre. Cahill, who blithely credits the Israelites with inventing history because the narrative books of the Old Testament have “a kind of specificity,” reveals his own slippery grasp on the specific. With the author’s last-minute qualification, the hinges fall off his history.