The most interesting concept that I will forever remember is that of Sigmund Freud. In particular his theories on the Id, Superego, and Ego. Two years ago I first read his theories and it struck me how powerful our unconscious is. That we make decision based on primal motives. It strikes me that we can have an uncurious so powerful and not beware of it at all. Although I find this interesting along with the rest of most modern psychologist I believe that he was not able to falsify most of his claims. A pioneer in the world of psychology I will forever know the man Sigmund Freud, but it will forever be tainted with the knowledge he may have been a little crazy and had some mommy issues.