The Buddhists called this prapañca (pronounced pra-PUN-cha), which roughly translates to “proliferation,” or “the imperialistic tendency of mind.” That captured it beautifully, I thought: something happens, I worry, and that concern instantaneously colonizes my future. My favorite Buddhist catchphrase, however, was the one they used to describe the churning of the ego: “monkey mind.” I’ve always been a sucker for animal metaphors, and I thought this one was perfect. Our minds are like furry little gibbons: always agitated, never at rest.