From Chapter One:

An explanation of emotions, and why they are so controversial in animals.

At first, all I saw was a white blur out of the corner of my eye. It was a long way away, maybe five hundred yards, and initially I wasn't sure what it was. Most of my focus was on my Border Collie Luke, who was running his fastest about two hundred yards away. I'd sent him on a long out run toward a flock of sheep during a "fun day" when herding enthusiasts get together and revel in dogs and sheep and the sloppy kisses of young puppies.

Many people there that day were serious competitors in herding dog tri-als, and were grateful for the opportunity to hone their skills away from home. Luke and I, however; were there just for the pure joy of it. We loved working together, Luke and I, finessing sheep gently and quietly across the countryside. A classic workaholic, Luke loved working sheep so much he had no interest in food, tennis balls, or even bitches in heat when there was a job to do. For me, watching my trustworthy black-and-white dog doing a perfect outrun on an emerald-green hill made my heart get bigger and my soul feel full. That's how I was feeling that morning as I watched my good old dog run perfectly and reliably toward the woolies on the far hill.