I guesss he's the smart one. He does not have to pedal.
He knows the trike always leads to someplace fun like the park or the beach for a swim. He does not want to get out of the basket at home sometimes, he wants to go ride more.
He is held in by a dog seat belt harness attached at the bottom with a swivel, to a four point harness, it's impossible for him to get out. But he can sit up turn around lie down etc. He likes being eye level with a big dog or a large goose.
He is the most famous dog on the four town 14 mile bike path, he's like the Pied Piper.
He's locally well known from being on state and local cycling club websites. I'm just the driver.