From Claude Steiner’s web page:

THE ADULT. When in the Adult ego state the person functions as a human computer. It operates on data it collects and stores or uses to make decisions according to a logic-based program.

When in the Adult ego state the person uses logical thinking to solve problems making sure that Child or Parent emotions do not contaminate the process. People may conclude from this that emotions are not good. But it only means that in order to be rational and logical we need to be able to separate ourselves from our emotions. It doesn’t mean that to be rational and logical is the best way to be at all times. In fact, just as an excluding Parent makes for an incomplete human being, so does an excluding Adult have the same deadening effect on people. People will also object: “I am an adult and I have emotions!” and they are right. Being a mature human being or grownup is not the same as being in the Adult ego state. Little children can be in their Adult and well adjusted grown-ups use their Parent and Child all the time.

The Adult computes all the facts fed into it. If the facts are up-to-date, then the Adult’s answers will be timely and more effective than the Parent’s solution. If the facts are incorrect, the Adult computer will produce incorrect answers. A very important function of the Adult is to predict outcomes and to provide a fact-based critique of the effectiveness of people’s behavior in the pursuit of their chosen goals. This fact-based, critical function is different from the value-based function of the Critical Parent.

Sometimes the Adult uses information which has its source in the Child or in the Parent and which may be incorrect. This is known as contamination. When a contamination comes from the Parent it is called a prejudice. For instance when someone assumes that women prefer to follow a man’s lead instead of making their own decisions this is data which comes to the Adult the from the Parent, and is a contamination because it is accepted as a fact without checking it against reality.

The same unchecked acceptance of information can occur with information fed by the Child in which case it is called delusion. A delusion is usually based on a Child fear or hope that is accepted as reality by the Adult. For instance when a person is convinced that he is being poisoned by the government this is probably based on his Child’s fears which the Adult accepts, rather than on fact. An extremely important process in transactional analysis is decontamination of the Adult.

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