<P> The social penetration theory (SPT) proposes that, as relationships develop, interpersonal communication moves from relatively shallow, non-intimate levels to deeper, more intimate ones . The theory was formulated by psychologists Irwin Altman and Dalmas Taylor in 1973 to understand relationship development between individuals . Altman and Taylor notes that relationships "involve different levels of intimacy of exchange or degree of social penetration". The social penetration theory is known as an objective theory, meaning that the theory is based on data drawn from experiments, and not from conclusions based on individuals' specific experiences . </P> <P> The social penetration theory states that the relationship development occurs primarily through self - disclosure, or intentionally revealing personal information such as personal motives or desires, feelings, thoughts, and experiences to others . This theory is also guided by the assumptions that relationship development is systematic and predictable . Through self - disclosure, relationships development follows particular trajectory, moving from superficial layers of exchanges to more intimate ones . Self - disclosure is the major way to bring a relationship to a new level of intimacy . </P>

The theory that the more we learn about a person the more we can predict about a person is known as