Implicit personality theory is the unquestioned assumptions an individual uses in thinking about the personality of another person; specifically, the characteristics that tend to be associated with each other in judging someone’s personality. For example, 'warm' usually goes with 'outgoing' ' sociable' and 'good-humored'; 'cold ' with 'withdrawn' , 'reserved' and 'humorless'. The concept is particularly associated with the American social psychologist fritz heider.
Definition