I’d been working on his “stay” command for weeks, trying to channel his boundless energy into something more controlled, especially indoors. The rain had been relentless for days, trapping us inside. Our living room had become an obstacle course of pillows and overturned chairs, the air stale with the scent of wet dog and dust. I’d read an article—one of those online things—about distance obedience training games and how they could tire a dog out mentally. It was supposed to be fun. A game. “Gus,” I said softly, nudging his side with my toe. He cracked open one eye, a sliver of warm, chestnut brown. “Get ready, buddy.” He was a creature of habit. He knew the routine. He hopped up, his tail a slow, questioning metronome, and sat at my feet. I held a piece of dried chicken breast, his favorite, and said, “Stay.” I walked backward, slowly, counting the steps. Three. Five. Eight. His eyes were locked on me, unblinking. He was a statue, his muscles quivering with the effort of staying put...