Demography denial, as I wrote here recently, is in fashion on the Israeli right. Faced with the argument that Israel can't rule over a large, disenfranchised Palestinian population and claim to be a democracy, the right's Alliance of Wishful Thinking invents smaller population figures and declares that—hooray!—Israel can annex the West Bank and maintain a Jewish majority. Inside the separate universe of the right, the numbers are responsively repeated until everyone knows they're true.

But with Israeli-Palestinian negotiations—just maybe, perhaps, hold your breath—about to resume, I should point out another Wishful Thinker trick: inflating the number of Israeli settlers. Relatively moderate demography deniers, such as Benjamin Netanyahu, use fanciful statistics to prove that the pre-1967 borders can't be the baseline for negotiations. Truly uninhibited deniers use the numbers to show that there's no point in negotiations at all. Journalists help out by behaving as if objectivity requires them to write down what politicians say without noting the nonsense.

Let's go back to May 2011. President Obama had just stated publicly that Israeli-Palestinian peace must "be based on the 1967 lines, with mutually agreed swaps." Netanyahu was furious. Speaking before Congress, he sought to prove that those borders had been erased by "dramatic demographic changes." Already, he said, "650,000 Israelis… live beyond the 1967 lines."In three ways, Netanyahu's comments were striking. First, he spoke as if the "demographic changes" happened by themselves, without government efforts. Second, he lumped Israelis living in the West Bank together with those in annexed East Jerusalem, violating a political taboo to make his point.

Third, news organizations reported what he said without checking the numbers. At the end of 2010, according to Israel's Central Bureau of Statistics, 311,000 Israelis lived in "the Judea and Samaria region"—the West Bank excluding East Jerusalem. The CBS is part of the Prime Minister's Office. Because of the same taboo, it doesn't report how many Israelis live in annexed East Jerusalem. But the independent Jerusalem Institute for Israel Studies processes government data to do just that. Its figure for the end of 2010 was about 191,000—producing a total of 502,000 Israelis in East Jerusalem and the rest of the West Bank. Bibi had added 148,000 extra settlers.

Netanyahu didn't say where he got his figures. But reports in the right-wing press seemed to suggest a solid source: the Interior Ministry's Population Registry, where all Israelis are listed, with their addresses. The Registry regularly produces tables of how many people officially reside in each settlement. I stress "officially." When people move, they don't rush to change their addresses, especially if doing so means losing benefits for living in a settlement. Young adults commonly stay registered at their parents' homes. Emigrants are still listed at their last address; if they die abroad, they live on in the Population Registry. In the Registry, the settler population is always a few percent above the more accurate CBS figure.

In January last year, a settler news site gave the new Population Registry figure of 342,000 West Bank settlers. "That does not include about 300,000 Jews" in East Jerusalem, it added. The first number was 5 percent above the CBS figure. The second number was 50 percent too high—and wasn't actually attributed to the Registry. In fact, the Population Registry couldn't have provided the figure; it only adds up how many people live in Jerusalem as a whole. The figure of 300,000 Israelis in East Jerusalem again popped up in the pro-Netanyahu paper Israel Hayom last summer. This June, hawkish columnist Guy Bechor cited it in Yediot Aharonot—and attributed it to the Registry. Bechor told me he took the number from previously published articles. He also wrote that the Registry lists 385,000 settlers in the rest of the West Bank. That's 19,000 more than what the Registry told me.

The same day Bechor's article appeared, the Washington Post published an interview with Jewish Home leader Naftali Bennett. Rounding upward, Bennett said 700,000 Jews lived over the Green Line—and argued that Israel should therefore annex most of the West Bank. The Post didn't question his figures.

The settlement population has indeed grown since Netanyahu's speech to Congress. But the Wishful Thinkers are still imagining as many as 150,000 extra settlers.

Believe me, the real number of settlers is problem enough—and every additional home Israel builds over the Green Line is another chip tossed on the table by a compulsive gambler with a losing hand. But the point of the land-swap option is to reduce the number of settlers who will have to move under a two-state agreement. The political and social cost of returning the rest of the settlers to Israel is exorbitant—but still much less than the price of creating a Bosnia-like single state from river to sea. The demography deniers want to prove that negotiations based on the 1967 lines are impossible. Don't be fooled by their numbers.