As a friend said, this is "its own entire category of sadness."
He was the best dog I've ever known. He made it tough to be a skeptic of the soul (whatever that means). It's so peculiar and irrational, our companionship with dogs. I loved Percy. It was an unsophisticated and simple and pure and enormous love. I will stretch my reason enough to have certainty always that he knew I loved him. And I will forever stretch my notion of love enough to be sure he loved me too. I'll miss him terribly and remember him always.