This paper focuses attention on the kinds of research assumptions that are present in the literature on language, and which can be found in the "myths" about family structure and motivation. Three major professions are concerned with describing the language and cognitive abilities of black children--(1) educators, who believe these children to be "virtually verbally destitute," (2) psychologists, who have "reconfirmed" initially that either these children don't talk, or, if they do, their speech is a "deterrent to cognitive growth," and (3) linguists, who have examined the language and found it a "well-ordered, highly structured, highly developed language system which in many aspects is different from standard English." The kind of responses that black children make in auditory discrimination tests are based on the sound usage they have learned in their environment, and do not reflect difficulty in discriminating. Because their syntax also differs from standard English, the psychologist, not aware of the rules of Negro nonstandard, has interpreted these differences not as the result of well-learned rules, but as evidence of "linguistic underdevelopment." The psychologist must learn to distinguish between the questions (1) Has this child acquired language? and (2) Has this child acquired competence in standard English? A reference list of recent works in linguistics and Negro studies is appended. (AMM)