On a cold February day John Kaag went for a jog down Lowell Street and had a heart attack. This was no case of an out of shape man pushing himself too hard. On the contrary, Kaag is a lifelong runner and a formidable racer. Running, for Kaag, was akin to an ascetic practice. He found inspiration in legendary mountain-climbing monks in Tibet who use physical discipline to reach beyond human limitation and embody a pure ideal.
