Using material from clinical practice and biographical data on acknowledged geniuses, I have shown that for the first-born child, male, the resolution of the pre-oedipal ambivalence toward the mother is particularly problematical. He has been the privileged only child until he is displaced and then has no older sibling to serve as an auxiliary object. The attempt at identification alternating between the new infant and the mother may be severely frustrated, leaving him destructively envious of the mother's (re)productive capacity. Under unfavourable circumstances, both the first-born's ability to work and to love may be seriously impaired. Under favourable conditions, his creativity may be enhanced and his love relations with women satisfactory.