So, last class, we discussed Freud. Now I want to turn to who's probably the second most famous psychologist ever, B.F. Skinner. Now, there's an important difference between these two scholars. Freud invented Psychoanalysis pretty much from scratch. But for Skinner, the situation was a bit different. The ideas were already there, by scholars like John Watson. Skinner came late into the field, but what he did was he package these ideas. He expanded upon them and he presented them as an articulated theory, the Theory of Behaviorism, to both the scientific community and the popular community. And just as Freud became a major figure when he was alive and after that, so too did Skinner. In 1960s and 1970s, he dominated American intellectual life with his radical and very, very interesting theory. So, Behaviorism has three main claims. The first is an emphasis on learning, a strong rejection of innate ideas or innate traits. For Skinner, everything you know, everything you are is the result of your experience. So, there is no human nature. We are infinitely malleable. Prior to Skinner, this idea was nicely summed up by John Watson, who said, "Give me a dozen healthy infants, well-formed, and my own specified world to bring them up in and I'll guarantee to take any one at random, train them to become any specialist I may select--doctor, lawyer, artist, merchant-chief, and, yes, even beggarman and thief, regardless of his talents, pensions, tendencies, abilities, vocations, and race of his ancestors." Now, you could see the appeal of this view, in some way and in a very traditional centers, very liberal view, because it says that you could be anything. Particularly, as Watson was explicit to point out, your race, and you might say now, your gender, doesn't matter. It's just your environment. Any one of us has infinite possibilities. A second theme of behaviorism is what you call Anti-metalism. So, behaviorist were very insistent on doing science. To a large extent, you could see behaviorism as the backlash against the excesses of Freud. So, Freud positive, all sorts of crazy invisible things. Defense mechanisms, and the id, and the super-ego, and the Oedipus complex, incredibly complex things that are internal to the head and are only revealed an exceedingly direct ways. The behaviorist said, "We want to do real science, and to do real science, we have to get away from these unscientific things like Freud talked about." Even unscientific things like, for behaviorist, desires, and wishes, and goals, and beliefs, and emotions, and stick to things we can observe, like stimulus, responses, feature of the environment, and so on. Only then can we become a true science. The third idea of behaviorism is that there's no interesting differences across species. Now, maybe a behaviors would concede a rat can't learn quite as quickly as a human. A pigeon is somewhat different than its learning capacities than a child. But for the most part, the principles of learning, and this is what I'm going to talk about next, the principles of learning proposed by a behaviorist are whole across all species. So, in essence, the only difference between a person and a rat in what they could come to know lies in the situations in which they are raised. As you can imagine, this is a radical, and shocking, and very interesting view.