credibility not possessed by earlier abstract models such as that developed by Freud. The Parent, Adult, Child (P-A-C) model After describing the context for his belief of the significance of TA, Harris describes TA, starting from the observation that a person's psychological state seems to change in response to different situations. The question is, from what and to what does it change? Harris answers this through a simplified introduction to TA, explaining Berne's proposal that there are three states into which a person can switch: the Parent, the Adult and the Child. Harris describes the mental state called the Parent by analogy, as a collection of "tape recordings" of external influences that a child observed adults doing and saying. The recording is a long list of rules and admonitions about the way the world is that the child was expected to believe unquestioningly. Many of these rules (for example: "Never run out in front of traffic") are relatively basic, often relating to immediate physical need or danger; others (E.g. "...you can never trust a cop", "...busy hands are happy hands") are more complex and concern more subtle or nuanced regions. Nevertheless, Harris asserts that both the former and the latter are 'recorded' in the child's memory in the same manner, as 'Parent' dictations, rather than actually understood concepts or philosophical precepts. In parallel with those Parent recordings, the Child is a simultaneous recording of internal events—how life felt as a child. Harris equates these with the vivid recordings that Wilder Penfield was able to cause his patients to re-live by stimulating their brains. Harris proposes that, as adults, when we feel discouraged, it is as if we are re-living those Child memories yet the stimulus for re-living them may no longer be relevant or helpful in our lives. According to Harris, humans start developing a third mental state, the Adult, about the time children start to walk and begin to achieve some measure of control over their environment. Instead of learning ideas directly from parents into the Parent, or experiencing simple emotion as the Child, children begin to be able to explore and examine the world and form their own opinions. They test the assertions of the Parent and Child and either update them or learn to suppress them. Thus the Adult inside us all develops over time, but it is very fragile and can be readily overwhelmed by stressful