In the 1950’s Eric Berne developed his theories of Transactional Analysis. He claimed that verbal communication, specifically face to face, is the most important factor to human social relationships and psychoanalysis. When two people meet each other, one of them will speak to the other. This he called the Transaction Stimulus. The reaction from the other person is called the Transaction Response. The person sending the Stimulus is called the Agent. The person who responds is called the Respondent. Berne also said that each person is made up of three alter ego states: Parent, Adult, and Child. The key point of transactional analysis is that people shift in and out of these 3 ego states.