As an aid to the same end, it is important to begin, at as early a time as possible, to train the child to occupy his mind actively with games and studies of educational significance. It is a fact which scarcely needs demonstration that the child in whom love of study and interest in subjects of study are developed at an early age will be a child unlikely to become unhealthily occupied with thoughts of himself. He will have too many and too strong external interests to have either time or desire for morbid self-communing. In fine, you may set this down as certain: the more you inspire in your children external interests in play and work, doing this partly by direct teaching and partly by setting them an example of industrious activity, the less reason you will have to fear that they will fall victims to the handicap of jealousy or to the nervous maladies resultant from any form of excessive preoccupation with thoughts of self. If, however, despite your best efforts, your child does develop jealous characteristics in marked degree, the safest and wisest thing you can do is to take him at once to a good specialist in the treatment of mental and nervous troubles. It may be that the jealousy is only the resultant of some unsuspected error of his upbringing, but it may also be symptomatic of some serious disorder requiring careful medical treatment. FOOTNOTES: [Footnote 7: In my "Psychology and Parenthood" pp. 223-227, will be found the details of a typical poltergeist performance.] [Footnote 8: "Educational Problems," vol. i, p. 363.] V SELFISHNESS "Jealousy," I stated a few pages back, "has its roots in selfishness, in an over-development of what may be called the ego-centric instinct." Aside from its role as a developer of jealousy, selfishness is indeed one of the major handicaps of childhood. Moralists have long urged on parents the importance of early training to prevent their children from becoming selfish. They have rightly pictured selfishness as among the greatest of human blemishes, giving character an ugly twist and making impossible that harmonious adjustment with other people which is indispensable to individual happiness and social progress. But it is not merely to be condemned from the moralist's point of view: it also is to be condemned from the physician's. Selfishness does much more than injure character: it may even ruin the health of those afflicted with it. To put the matter briefly, training against selfishness is imperative in early life, if only as a safeguard against the functional nervous and mental maladies so common to-day.