“…There are three sources of evidence here. In the field of mental testing, investigators have used the Binet test (Keir, 1945;Platonow, 1933;Spiegel, Shor, & Fishman, 1945), the Wechsler-Bellevue Intelligence Scale (Kline, 1951), the Otis Performance tests (Kline, 1950), the Word Association Test (Dittborn, 1951;Keir, 1945), and various kinds of motor tasks, such as drawing a man, handwriting, etc. (Orne, 1951;Platonow, 1933).…”