Reading on my back deck on an unconscionably warm winter day, I’m distracted by our outdoor cat, Butter, as he skitters, leaps, pounces, and slides across the dead leaves strewn on the planks. I can’t see what he’s after, but I figure it’s a moth or a skink, both regular parts of Butter’s diet. We feed Butter well enough, and he doesn’t need to supplement with insects, reptiles, or rodents. He appears to enjoy the chase for its own sake, as a welcome relief to the ennui that creeps over felines on a sultry afternoon. He seems playful, and purposefully so.