Twins—Observations of Environmental Influences on their Development

Before attempting the psychological study of the relationship of twins to each other, it is necessary to examine, as far as possible, outside circumstances which might have a bearing on the subject of twins and therefore have an indirect influence on them. The mother's relationship to twins must be investigated for influences dissimilar to those which she has on her other children. The brother and sister relationship towards twins may have components which are not present in their relationship otherwise. The investigation includes not only close emotional ties but the more casual and general contacts, which make up the world in which twins live. Here the influence may not only work through direct contacts but through more subtle and indirect ones, as for instance through the general view that all twins love each other. There is still another aspect to keep in mind, the effect of twin fantasies on twins. As I have recently shown1 many people have had a period in their lives when they enjoyed the fantasy of having a twin. It would be interesting to know how far their fantasies determine the behavior of these persons when they meet twins in reality; whether these fantasies are not played out on twins, encouraging and perhaps enforcing them to take over the fantasied roles. As a result the twins might find the compelling character of these fantasies even more powerful than the effect of their own twin relationship.

To observe adults when they are unexpectedly confronted by a pair of boy or girl twins gives striking evidence of one form of outside influence on twins. Adults generally show surprise and interest when they meet twins of a young age. They gaze from one twin to the other, making mental comparisons. Often their observations are accompanied