ABSTRACT
IN TRYIN G T O SUMMARIZE a lot of information abou t hereditar y factor s i n human psychological differences , on e i s overwhelmed b y th e mas s of detail s tha t de -mand som e organization . I n thei r admirabl e boo k o n Behavior Genetics (1960), Fulle r an d Thompso n se t a difficul t standar d t o follow . Thi s pape r w i l l
concentrate o n materia l no t availabl e a t tha t time , mos t o f i t fro m twi n studies .
N o attemp t w i l l b e mad e t o presen t detail s o n th e man y psychologica l test s em -
ployed i n the studie s reviewe d here , becaus e t o d o s o woul d mak e thi s pape r fa r
too long . The intereste d reade r is referred t o th e reference s give n for these studies .
