Here’s a philosophical question. Some pinball machines reward high scores with free replays. And in states with anti-gambling statutes, some prosecutors crack down on this feature, saying that it constitutes gambling.

Is this a coherent argument? If pinball is legal, then can more pinball be illegal?

“The prosecutors … believe that ‘more of the same’ can be too much of a good thing, and rather than multiply legal acts, actually cross the line of legality,” writes Peter Suber in The Paradox of Self-Amendment.

“A quantitative change becomes at some point a qualitative change, just as lowering the temperature of water by degrees gives us nothing but cold water for a while, and then suddenly gives us ice.”