IN recent years there has been a phenomenal increase in the number of “special children.” The term comes from the educational establishment, where it is used to refer to all children who have unusual learning problems not readily explainable by either medical or sociological factors (blindness, say, or ignorance of the English language). A study by the Rand Corporation, released in February 1974, asserts that some nine million Americans under the age of 21 (roughly 10 per cent of the population in that age bracket) suffer from various forms of “learning disability.” By January 1975 informed observers already spoke of a “learning disability epidemic,” allegedly affecting up to 40 per cent of school-age children.