ABSTRACT
In the academic year 1939-40, I took a course in individual differences (regularly taken by all psychology majors at Minnesota in those days) from one of the “greats” of applied psychology, Donald G. Paterson, a founder of what was then called the “student personnel movement.” A main theme of Paterson’s lectures was that there are no types of persons, that categorical terminology (e.g., “introvert,” “bright,” “thin”) is merely a convenient—and sometimes careless—way of demarcating rough regions on what are in reality quantitative traits, dimensions, or factors. He pointed out, for instance, that Jung had a typology of introverts and extroverts, but then had to add ambiverts, which is where most of us are on a bell-shaped curve of the dimension introversion-extroversion. Paterson said that there was a marked difference between American and European psychologists in this respect, the Europeans being fond of typology and the Americans, with some exceptions, suspicious of the concept. Big typological names in Europe were psychiatrists Kretschmer and Jung, and to some extent Freud; and psychologists such as Jaensch and Klages. Paterson did allow for exceptions to his doctrine, especially in the area of intelligence. There is an association between incidence of the higher levels of mental deficiency or borderline IQ and lower social class, whereas much lower IQ levels (in the idiot and imbecile ranges) are independent of parental SES. Typological language in the upper levels (e.g., ‘moron,’ ‘borderline deficient,’ ‘dull-normal’) he considered analogous to terms like ‘introvert,’ ‘domineering,’ or ‘thin,’ having no true typological or taxonomic significance. Moron, borderline, and dull-normal children he held to be simply the low end of the normal distribution of the polygenic determiners of g; whereas he thought the lowest IQ groups represented Mendelizing, karyo-typic, or developmental anomalies, similar in that respect to the valid typologies of organic medicine. On this view the reason for the association of the non-typological mental deficiencies with social class was the transmission of low IQ polygenes from parents, plus a (slight, he thought) influence of poor environmental stimulation in the home.
