The Five Factor Model has taken various forms over the years but has more recently taken the form of the OCEAN model of McCrae and Costa and the Big Five model of Goldberg. Both of these models although derived from different methodologies are an attempt to explain human behaviour using traits. There has been much debate as to whether these conceptual models do in fact explain behaviour or whether they are just descriptive of behaviour.
Carr and Kingsbury (1938) defined "trait" as "a conceptual attribute or definition of the reactive nature of an individual" where "the nature of an individual is defined on the basis of certain observable behaviour characteristics....which society regards as of sufficient importance to identify and name and.....which are regarded as expressions or manifestations of the constitutional nature of the individual". They regarded "traits" as "conceptual realities" akin to "engrams, nerve traces and neural modifications" which cannot be observed other than through their behaviour manifestations. …