Imagine this: You’re putting together a nifty jigsaw puzzle—say, your favorite Elvis montage painting on black velvet—when one of the pieces suddenly morphs into an entirely different shape. Aside from the unnerving quantum-mechanical implications of this event, you’ve got a problem—the surrounding pieces no longer fit. You could try to alter those pieces (a troubling prospect, since it will require distorting all the ones around them) or give up on the puzzle entirely—unless, of course, you could get the little sucker to resume its former shape and size.

This sort of situation arises in every human life. We live in social systems—families and neighborhoods, offices and […]