Abstract
Primary specific characteristics of psychological reactions, typical of the individual and undoubtedly influencing the formation and dynamics of his character, can be defined as “psychological constitution.” Experimental study of peculiarities of an individual's set by the method elaborated by D.N. Uznadze and his school was chosen as a way to elicite psychological constitution. The manner in which the subject creates a model of the situation and the rate at which this model is destroyed when it fails to correspond to the perceptual data, appear to be the central question. A conceptual approach is suggested for evaluation of experimental data as characteristics of the individual's psychological constitution. It turns out thereby to be possible, theoretically and experimentally, to single out 8 basic types of psychological constitutions, or “primary psychotypes.”