The Undoing Project: A Friendship that Changed the World(43)
But that day something shifted inside Amos. He left Danny’s seminar in a state of mind unusual for him: doubt. After the seminar, he treated theories that he had more or less accepted as sound and plausible as objects of suspicion.
His closest friends, who found the change in him shocking, assumed that Amos had always had his doubts. For instance, on occasion he spoke of a problem experienced by Israeli army officers when they led troops through the desert. He’d experienced the problem himself. In the desert, the human eye had trouble judging shapes and distances. It was difficult to navigate. “That was something that really troubled Amos,” said his friend Avishai Margalit. “In the army you had to navigate a lot. And he was very good at it. But it gave even him trouble. Traveling at night, you’d see a light in the distance: Was it close or far away? The water appeared as if it were a mile or less away—then it would take many hours to walk to it.” The Israeli soldier couldn’t protect his country if he didn’t know the country, but the country was difficult to know. The army gave him maps, but the maps were often useless. A sudden storm could drastically alter the desert landscape; one day the valley was here, the next day it was over there. Leading soldiers in the desert, Amos had become sensitive to the power of optical illusion: An optical illusion could kill. Israeli army commanders in the 1950s and 1960s who became disoriented or lost their way also lost the obedience of their soldiers, as the soldiers understood that there was a short step from being lost to being dead. Amos wondered: If human beings had been shaped so carefully for their environment, why was their perception of that environment still prone to error?
There’d been other signs that Amos was less than wholly satisfied with the worldview of his fellow theorists in decision making. Just a few months before he’d spoken at Danny’s seminar, for instance, he had been called back into the army, on reserve duty, and sent to the Golan Heights. There was no fighting to be done just then. His job was simply to command a unit in the newly acquired territory, gaze down upon Syrian soldiers, and judge from their movements if they were planning to attack. Under his command was Izzy Katznelson, who would go on to become a professor of mathematics at Stanford University. Like Amos, Katznelson had been a boy in Jerusalem during the 1948 war of independence; scenes from that year were seared into his memory. He remembered Jews running into the houses of Arabs who had fled and stealing whatever they could. “I thought, those Arabs are people like me: They didn’t start the war and I didn’t start the war,” he said. He’d followed the noise inside one of the Arab houses and discovered yeshiva boys destroying the Arabs’ grand piano—for the wood. Katznelson and Amos didn’t talk about that; those were events best forgotten.
What they talked about was Amos’s new curiosity about the way people judged the likelihood of uncertain events—for instance, the probability of an attack at that moment by the Syrian army. “We were standing looking at the Syrians,” recalled Katznelson. “He was talking about probabilities, and how do you assign probabilities. He was interested in how, in 1956 [moments before the Sinai campaign], the government had made some estimates that there wouldn’t be a war for five years, and other estimates that there wouldn’t be a war for at least ten years. What Amos was pushing is that probability was not a given. People do not know how to do it properly.”
If, since his return to Israel, there had indeed been a growing pressure along some fault line inside Amos’s mind, the encounter with Danny had triggered the earthquake. Not long afterward, he bumped into Avishai Margalit. “I’m waiting in this corridor,” said Margalit. “And Amos comes to me, agitated, really. He started by dragging me into a room. He said, You won’t believe what happened to me. He tells me that he had given this talk and Danny had said, Brilliant talk, but I don’t believe a word of it. Something was really bothering him, and so I pressed him. He said, ‘It cannot be that judgment does not connect with perception. Thinking is not a separate act.’” The new studies being made about how people’s minds worked when rendering dispassionate judgments had ignored what was known about how the mind worked when it was doing other things. “What happened to Amos was serious,” said Danny. “He had a commitment to a view of the world in which Ward Edwards’s research made sense, and that afternoon he saw the appeal of another worldview in which that research looked silly.”
After the seminar, Amos and Danny had a few lunches together but then headed off in separate directions. That summer Amos left for the United States, and Danny for England, to continue his studies of attention. He had all these ideas about the possible usefulness of his new work on attention. In tank warfare, for instance. In his research, Danny was now taking people and piping one stream of digits into their left ear and another stream of digits into their right ear, and testing how quickly they could switch their attention from one ear to the other, and also how well they blocked their minds to sounds they were meant to be ignoring. “In tank warfare, as in a Western shootout, the speed at which one can decide on a target and act on that decision makes the difference between life and death,” said Danny later. He might use his test to identify which tank commanders could best orient their senses at high speed—who among them might most quickly detect the relevance of a signal, and focus his attention upon it, before he got blown to bits.
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