This study offers a definition, description, analytical theorisation and critical discussion concerning the relationship between internal and external conversation. 'Internal conversation' refers to the inner dialogues that individuals have with themselvesÂ· about themselves and the social environment, while 'external conversation' refers to those parts of internal conversation that the individual shares with others. The central question of this research, concerning the relationship between internal and external conversation, derives from a common observation which remains unanswered: why do people produce different external conversations or different actions or responses when they face similar social situations? In other words, why do people react in different ways to analogous stimuli or circumstances? The individual constantly interacts in a specific way with both her external environment and herself; this process links the inner and outer cosmos of each person. This relationship is formed according to specific phases and operations, and it constitutes an 'agential filter' comprised of certain stages that enable the individual to relate her internal and external conversations. The individual uses a specific process in order to decide which part of her internal conversation she will externalise. This process is defined as 'mediation' and operates differently for each individual. It does, however, have a common aim: the main objective of mediation is to achieve a subjectivelydefined degree of 'inner balance' between her inner and external world which is satisfactory to her.