Ben Ratliff is running. He’s off the cinder path encircling Van Cortland Park’s Parade Ground, not far from his home in the Bronx, N.Y. He enters the woods. Earphones in, he listens to Eric Dolphy’s ...

In this case, it makes sense to begin in the middle — that is, several miles into a run in Van Cortlandt Park in the Bronx, with the blues or hardcore or even traditional Japanese flute music blasting ...