I'm all for people risking their lives and getting a thrill out of jumping from anywhere in the world. But I'm not a fan of people who get their dog along for the ride. As fun as it may look, I'm pretty sure the dog—who doesn't understand what the hell is going on—is not a fan of it either, even while he looks calm.
The way I see it, a dog is not a toy. A dog is not a teddy bear. A dog is not a character from a movie. You can't anthropomorphise them just because you saw a Disney movie when you were a kid. A dog is an animal who can't understand what's going on most of the time and, still, they trust us with every fibre of their beings.
So when Dean Potter—apparently a "famous rock climber, high-liner and human flyer"—gets his dog Whisper for a BASE jump at the Eiger, Switzerland, I'm not amused, even while I'm curious to see Whisper's reaction. My logic goes like this: Dogs weren't designed to fly. Would a dog choose to fly if you give him the choice? I don't know. But since they weren't designed to fly and they can't make that choice, let's assume that, if you asked them and they could talk, they would probably say "no, fuck you. You go jump. I will watch from here, thank you very much."
And yes, Whisper is jumping of joy when he's on the ground, but that's probably from the anxiety of being up there and the relief of being back in the ground—not from the fun of it.