Grigori Guitchounts studied biological intelligence as a neuroscientist at Harvard; he now builds and investigates the artificial kind. I was in the final months of my Ph.D. in neuroscience at Harvard when an email arrived from an animal care technician. GRat44, one of my lab rats, was sick. “The teeth are overgrown, and the animal is in poor flesh,” the message read. “Euthanasia required within 5...