In his book, Psychology and the Soldier, which gives a critical estimate of the psychologist's contribution during the last war, Bartlett (1) makes an interesting statement which takes on new meaning at the present time. Commenting on the fact that intelligence tests may safely “rule out a man” from participation in activities which may endanger the group, he queries whether a man can as simply be “ruled in” for filling a responsible position. “For practical purposes,” Bartlett says, “temperament is a more important factor in success than intelligence, as the latter is understood in the mental test movement. Slight variations in temperament may make a bigger difference to a man's practical value in any social organization, such as an army, than large variations in intellectual processes. No doubt much can be done by psychological examination to discover a man's real temperamental qualities; no doubt a psychologically skilled or a psychologically trained observer can detect such qualities speedily and with reasonable accuracy. But the satisfactory direct temperament test has yet to be devised, and very likely never will be found.”