My son Geoff recently participated in a “homeless simulation.” He spent three days and two nights living on the streets of his city, sleeping outside in below freezing temperatures. Without food, money, or shelter, he relied on the kindness of strangers for his basic needs. On one of those days his only food was a sandwich, bought by a man who heard him asking for stale bread at a fast-food restaurant.

Geoff told me later it was one of the hardest things he’d ever done, yet it profoundly impacted his outlook on others. He spent the day after his “simulation” seeking…