In 2016, 24 people at the US Embassy in Cuba reported symptoms like dizziness and nausea after hearing high-pitched noises. Investigators speculated it was some kind of “sonic weapon,” leading to a media frenzy.

What are the limits on human compassion? That’s a question that Paul Slovic, a psychologist at the University of Oregon, has studied for years. And the answer is partly why human catastrophes—like the fact that 65.3 million people have been displaced from their homes…