“Danny explained, “Reforms always create winners and losers, and the losers will always fight harder than the winners.” How did you get the losers to accept change? The prevailing strategy on the Israeli farms – which wasn’t working very well – was to bully or argue with the people who needed to change. The psychologist Kurt Lewin had suggested persuasively that, rather than selling people on some change, you were better off identifying the reasons for their resistance, and addressing those. Imagine a plank held in place by a spring on either side of it, Danny told the students. How do you move it? Well, you can increase the force on one side of the plank. Or you can reduce the force on the other side. “In one case the overall tension is reduced,” he said, “and in the other it is increased.” And that was a sort of proof that there was an advantage in reducing the tensions. “It’s a key idea,” said Danny. “Making it easy to change.”