The historical bases for the study of meaning in language are considered. More specifically, the psychology of language development is discussed in terms of a dialectic of "mechanistic" psychology based on sensation and movement, and "mentalistic" psychology, based on internal processing of meanings. The discussion of mechanistic psychology includes sensory-empiricism, psychological elements and connections, stimulus-response mechanisms, mediational mechanisms, associative meaning, semantic differentials, and communications processes. The discussion of mentalistic psychology includes rationalism, triadic sign systems, generative linguistics, cognitive psychology, and quality growth modes. The discussion of dialectic psychology includes Rubinsteins's double interaction theory, the changing individual in the changing society, and the author's ideas of what has to be done to study language. The closing is an outline of the book in which this paper is included and a summary of ten conclusions arrived at from the description of the philosophical basis for a dialectic study of meaning and its acquisition.