Ivan Petrovich Pavlov, “The Works of the Digestive Glands”, 1897 was a “psychological physiology” of conditioning. Psychology is a soft, science-fiction subject; and, Physiology is a hard, science-fiction subject. Ivan Petrovich Pavlov’s, “The Works of the Digestive Glands “, 1897 is known to everyone today. This allows “psychological conditioning” to be the plot storyline of many science fictions. The research of Pavlov feeding his dogs with (and with “bells” ringing) conditioned the dogs to “expect” food (expect meaning “salivate”). The “conditioning” of mammals (dogs, humans, and others) is the kind of Science that defines what Science Fiction is. Ivan Petrovich Pavlov, “The Works of the Digestive Glands”, 1897 is historic; that said, if you are dieting don’t reread this book.