Betty and I are walking down the sidewalk of a rather busy street when a car screeches to a halt in the middle of the road and a kid jumps out and asks: “Can I pet your dog sir?” And Betty makes yet another friend. I don’t get it. What is this mysterious attractive force that Betty possesses? I don’t recall studying any such thing in the physics classes I took. Is it some sort of undiscovered force? The Betty force? Do they give Nobel Prizes to dogs?