A cat walking across a room swerves suddenly and walks carefully around something we can’t see. We shrug, smile, and remark that cats are always doing that. Our hitherto amiable dog suddenly develops the irritating habit of barking and growling violently at certain innocent passersby. We still shrug, wonder what’s got into the mutt, and pass it off. Mr. Dick argues with frightening urgency that if we are wise, we wilt immediately investigate these oddities of animal behavior.
