A method for identifying reasoning modes and assessing the relative preference of a reasoning mode of a test subject ("investigator"). More specifically, dichotomous pairs of terms are developed wherein each pair contains one term predominantly associated with a linear reasoning mode, and another term predominantly associated with a complexity reasoning mode. The pairs of terms are presented to the investigator for selection by the investigator as to which of the two terms of each term pair best describes, in the judgment of the investigator, the investigator's reasoning behavior. New terms may be tested for psychometric strength against the empirical record of a plurality of previously employed terms. Words and images may be compared to a library of terms to form new terms whose suitability as terms associated with a distinct reasoning mode is then evaluated. The identification of reasoning modes may include a method for assessing the association of a mental capacity with a reasoning mode. Problems may be abstracted and compared with a library of models to determine which reasoning mode is most appropriate for use in addressing each problem. Certain words describing dichotomous qualities and aspects of linear reasoning and complexity reasoning modes are provided.