Scarcity is humanity’s great motivator. This has been true forever, since back when we were basically apes: The most important resources—food, shelter, mates—were the ones that were most in demand. Shortage meant value, and being attuned to value meant staying alive. We learned to focus on the rare thing at the expense of what was around it—psychologists call this “tunneling”—and to prioritize avoiding loss over gaining rewards. It was typically smarter to fight for something everyone else