How even the smallest acts of kindness make us happier and healthier

Kindness is also contagious—and science backs that up. This entrepreneur rediscovered that phenomenon when her community pulled together after a wintry blast knocked out power.

When a windy arctic blast raged through the Northeast U.S. this past winter, more than 600,000 people lost power for days. I was one of them. Because we don’t own a generator, our family toughed it out in the freezing cold without power. It tested everyone’s mettle. But when I stepped back from my extreme discomfort for a few moments...