CAPITALISM relies on inequality. Like differences in other prices, pay disparities steer resources — in this case, people — to where they would be most productively employed…

Yet the increasingly outsize rewards accruing to the nation’s elite clutch of superstars threaten to gum up this incentive mechanism. If only a very lucky few can aspire to a big reward, most workers are likely to conclude that it is not worth the effort to try. The odds aren’t on their side.

Inequality has been found to turn people off. A recent experiment conducted with workers at the University of California found that those who earned less than the typical wage for their pay unit and occupation became measurably less satisfied with their jobs, and more likely to look for another one if they found out the pay of their peers. Other experiments have found that winner-take-all games tend to elicit much less player effort — and more cheating — than those in which rewards are distributed more smoothly according to performance.

Ultimately, the question is this: How much inequality is necessary?