“…Almost all children given the psychoneurotic test (8 pairs) fell into the normally stable group (Table 9) , The scores of the twins varied only slightly in most instances, but in two cases there was a marked difference. In one pair (Case 9) both twins were very unstable emotionally (25,14) and 25, respectively (normal 6 to 15). In this case the former was in the opportunity class while the latter was in 4B, though-the intelligence quotients were identical.…”