Lanier gets peevish even being asked to identify a moment when machine intelligence might become convincingly human. “This idea of a certain year is ridiculous. It’s a cultural event. It’s a form of theater. It’s not science. There’s no rigor. It’s like saying, ‘When will hip-hop really be an art form?’ To take it seriously is to make yourself into a moron. It came from one of the most brilliant technical minds”—Turing—“so we give it credence.”

But still, I pressed him, during some of our lifetimes won’t computers be totally fluent in humanese—able to engage in any kind of conversation? Lanier concedes some ground. “It’s true, in some far future situation, we’re going to transition. . . . I think it’s very hard to predict a year.” Approximately when? “I think we’re in pretty safe territory if we say it’s within this century.” Which is much sooner than I figured he’d meant by “far future.”

So crossing that practical threshold (machines perfectly simulating all kinds of human interaction) does seem inevitable and nearish. But the scientific threshold (computers actually duplicating human intelligence) is probably much further away. After a decade overseeing the Allen Institute for Brain Science, Paul Allen doesn’t think we’ll get there until after 2100. He threw the gauntlet down in an M.I.T. Technology Review article called “The Singularity Isn’t Near.” The brain is a machine, sure, but the complexities of its operation remain mysterious—way, way beyond our full practical understanding. In fact, the neuroscience breakthroughs of the past 20 years are revealing how much we don’t understand, vastly expanding the scale and scope of the known unknowns. “By the end of the century,” he wrote, “we will still be wondering if the singularity is near.”

WHITEWASHING THE FENCES

Neither the Singularity believers nor the Singularity doubters define themselves in conventionally political or religious terms. They’re all secular rationalists. They’re all liberals in the old-fashioned sense—capitalists interested in alleviating misery efficiently. Yet the schism that divides them is essentially sociopolitical and religious.

First, the politics. Diamandis talks a lot about “the grand challenges” of “the billion-person problems,” by which he means the wretched conditions in which the world’s poorest people live. “How many equivalents of Da Vinci and Edison,” he said to me, “have come into existence in parts of the world without communications and are never heard from?” When I sat down with Kapor near his weekend home in Healdsburg, a yuppified old Sonoma County town north of San Francisco, he said almost exactly the same thing: “The amount of sheer genius that is being completely wasted—who knows what brilliant discoveries would be made if we weren’t throwing so much away?”

Rather than losing sleep over potentially catastrophic downsides to the whiz-bang future, the Singularitarians seem most concerned about misguided humans preventing its full flowering. Peter Thiel is the rare downbeat Singularitarian—pessimistic only because he worries that environmentalism and politics and regulation are already slowing innovation. (He is a supporter of libertarian causes and the right-wing Club for Growth.)

Being technologists, they tend to underappreciate the nitty-gritty quirks and complications of behavior and culture that shape history. An unalloyed engineering paradigm, Lanier explained, assumes “a kind of a linear, clean quality to progress that’s just never true. Technologists tend to think of economics as unimportant because it always favors us. This idea that everything will become cheaper all at once is stupid.”

Kurzweil as much as admits he only deeply cares and knows about technology and its theoretical impacts, about political economy and human psychology not so much. Concerning his prognostication ability—his 1999 prediction of a “continuous economic expansion and prosperity” through 2009, for instance, which he claims is correct—he told me that “when it gets into implications that include regulatory and social responses, it can be less accurate.” He and Diamandis gloss over economics and politics in their books. In the latest one, Kurzweil mentions a Gallup poll that found a majority of Americans believe life will be worse for their children—but then simply says they’re wrong, and trots out all the happy trend lines of the last 50, 100, and 1,000 years to prove it. When I asked Singularity University’s C.E.O., Rob Nail, if the curriculum touches at all on politics or economics, he said not really, but they are “in discussions” about adding those subjects.