For me, I was around 50. I suddenly realized that more highway was behind me than out front, more life lived than yet to go. Maybe I had just been running too fast to notice how far I had traveled, but nevertheless, I paused the pace and soaked it in. This realization is so common, we have a name for it—a mid-life crisis. Dartmouth College professor David Blanchflower conducted an extensive study that suggests that…