Psychoanalytic developmental theory has been profoundly influenced by recent observational research on infants. Although it is commonly held that these new data refute earlier theories of infancy, an examination of the evidence indicates otherwise. Much of the disagreement between the two is based on differences over the definition of such concepts as "self" and "self/other differentiation" and over strategies of theoretical inference. Inferences about the subjective experience of infants are best viewed as theoretical postulates rather than empirical statements or metaphors.