BEHAVIORAL DEFINITIONS TIMELINE 1845-1975

1845
Esquirol: "Idiocy is not a disease, but a condition in which the intellectual faculties are never manifested, or have never been developed sufficiently to enable the idiot to acquire such amount of knowledge as persons of his own age and placed in a similar circumstances with himself are capable of receiving" (1845, p. 446).

This French physician (Itard) believed that the mind was a blank paper to be written on by experience. Therefore, the mentally retarded would be those persons who had few or inferior developmental experiences (Kolstoe, 1970, p. 13).

1846
Howe: "…'feebleminded' persons who ranged in level of incapacity from those with reason enough for simple individual guidance plus normal powers of locomotion and animal action, to 'mere organisms'" (from President's Committee on Mental Retardation, 1976, p. 2).

1908
The Royal College of Physicians (1908, p. 324), defined and classified retardation in a similar way: Idiots were defined as persons so defective that they are unable to guard themselves from common physical dangers; imbeciles were defined as persons capable of guarding themselves against common dangers but incapable of earning their own living; and feebleminded persons were defined as those capable of earning a living in favorable conditions but unable to compete on equal terms with normal persons or to manage their own affairs with ordinary prudence.

1949
Walling writes of the condition as one that affects the "capacity of social and economic adjustment" (1949, p. 13).

1951
Kirk and Johnson suggested classifying mentally retarded children as mentally deficient or as mentally handicapped. Mentally deficient children "require care and supervision by their families or by the state" (1951, p. 7) because they are unable to manage their own affairs. "It would not be expected that such children could be educated to care for themselves at the adult level…" (1951, p. 9). Mentally handicapped children have a more favorable prediction: "The prognosis of social competence under favorable circumstances would differentiate the mentally handicapped child from the feeble-minded [mentally deficient] child who cannot be educated to become socially competent" (1951, p. 10).

1954
Benda regards the retarded person as one who "requires supervision, control and care for his own welfare and the welfare of the community" (1954, p. 1115).

1960
Ingram defined the trainable or severely retarded as ranging in IQ from 25 to 49 and as being "uneducable in terms of academic skills and occupational adequacy" (1960 p 17).

1962
The President's Panel on Mental Retardation indicates the retarded as being "significantly impaired in their ability to learn and adapt to the demands of society" (1962, p. 1).

1963
Masland describes the mentally retarded individual as one who is "incapable of performing at the level required for acceptable adjustment within his cultural environment" (1963, p. 286).

1966
Bijou: "A retarded individual is one who has a limited repertory shaped by events that constitute his history" (1966, p. 2, italics in original).

1969
Poser: Mental retardation means that "the individual functions at a level below that which is expected for his age" (1969, p. 1).

1971
The National Association for Retarded Children: "the mentally retarded person is one who, from childhood, experiences unusual difficulty in learning and is relatively ineffective in applying whatever he has learned to the problems of ordinary living; he needs special training and guidance to make the most of his capacities, what ever they may be." (Waite, 1971, pp. 5-6).

1972
Kirk: "The trainable mentally retarded child has been defined as one who because of subnormal intelligence,is not capable of learning in classes for the educable mentally retarded but who does have potentialities for learning: (1) self care; (2) adjustment to the home or neighborhood,; and (3) economic usefulness in the home, a sheltered workshop, or an institution" (1972, p. 221).

Kirk: "The 'educable mentally retarded child' is one who, because of slow mental development, is unable to profit to any great degree from the program of the regular schools, but who has these potentialities for development: (1) minimum educability in reading, writing, spelling, arithmetic and so forth (2) capacity for social adjustment to a point where he can get along independently in the community and (3) minimum occupational adequacy such that he can later support himself partially or totally at a marginal level. The term educability then refers to minimum educability in academic, social and occupational areas" (1972, p. 191).

1975
R. M. Smith and Neisworth: "Mental retardation" is best defined as inadequate intellectual functioning for independent functioning in society. (1975, p. 42).

Source: Neisworth, J.T. & Smith, R. M. (1978.) Figure 4-7, Chronological Listing of Definitions. In Retardation: Issues, Assessments, and Intervention (pp. 66-69). New York: McGraw—Hill, Inc