The Aspen gathering consisted of venture capitalists and Washington ­strategists, the kind of people who make predictions based on market conditions and political intelligence. Smith, by contrast, is an expert on Spinoza, Hegel and Leo Strauss. He’s preoccupied not with economic leading indicators, but with a handful of great thinkers.

Smith is a beloved lecturer at Yale. He’s superb at bringing abstract ideas to life, even if his colloquial style can be jarring on the page (“Here is where the Kantian rubber meets the road”). He’s divided his survey into two parts: The first covers writers he regards as quintessentially “modern” in their attitudes, from Machiavelli to Hegel; the second covers writers more attuned to pessimistic doubts about the modern world, including Rousseau, Tocqueville, Nietzsche and the two 20th-century critics of the Enlightenment that he perhaps most admires, Isaiah ­Berlin and Leo Strauss.

For Smith, the “modernity” of his book’s title connotes (among other things) a handful of core convictions: the value of freedom and equality; the importance of being able to think for oneself; the real possibility of universal enlightenment. Like Tocqueville, Smith worries that these liberal convictions, though superficially benign, nevertheless issue in a debased form of life that he associates with “low-minded materialism, moral cowardice and philistinism.” It’s as if an expansion of popular optimism about the future, alongside an amelioration of everyday life for ordinary people, must produce, as its shadow, a supine complacency, conjoined with a lazy form of what-me-worry ­nihilism — a democracy of dunces.

Allan Bloom made a somewhat similar argument in “The Closing of the American Mind.” Smith happily lacks Bloom’s bile, and is far more catholic in his taste. He includes a series of close readings not just of theoretical texts, but also of fictional works, among them an elegiac essay on “The Leopard,” the historical novel by ­Giuseppe di Lampedusa, published in 1958 and later filmed by Visconti. As a good college lecturer must be, Smith is skilled at haute vulgarisation. But like Bloom (and Lampedusa, for that matter), he’s deeply suspicious of the demotic drift of modern culture. “Its goal,” he writes, summing up Leo Strauss’s contemptuous attitude, “is not contemplation but ‘universal enlightenment’ ” — the scare quotes say it all.

As for the relationship of modernity to the bourgeois world adverted to in Smith’s subtitle, the most important recent work on that topic is surely Jerrold Seigel’s “Modernity and Bourgeois Life: Society, Politics, and Culture in England, France, and Germany Since 1750” (published in 2012, but ignored by Smith). A major work of comparative history, Seigel’s book ­traces in detail the rise of new networks of commerce, power and culture: Merchants and bankers exploit expanding worldwide trade routes; diplomats and statesmen create new forms of international relations (including the possibility of world wars); while scientists and scholars exchange knowledge and ideas without regard to borders. The result is a great global marshaling of human capacities, for purposes that remain undefined and indefinite.