View report page

98
All factors have to be weighed, it is not practicable to say that because an individual is 3, 4 or
more years retarded in psychological or educational tests he is ipso facto defective, on the other hand a
subject may in many tests pass up to the average of his age and yet in other ways indicate that he
lacks the wisdom to care for himself.
The law recognises four grades of mental deficiency, which, however, to some extent overlap.
Interpreting these definitions in the terms of mental age as ascertained by tests of various kinds,
it has been the practice to regard those of later school age and over who show a mental age of less than
3 as being idiots, those with a mental age between 3 and 7 as imbeciles, and those who show a retardation
of 3 years or more but with a mental age of above 7 as feebleminded. It was, however, at once
clear that the latter definition was of limited application to those of mature years.
Experience under the Mental Deficiency Act, in London, seems to show that no young person
with a mental age under 8 is able to fend for herself, some with a mental age of 8 are able to carry
on provided they can secure a sympathetic employer and are carefully supervised, while those with a
mental age of 9-10 are often able to fend for themselves with a reasonable degree of supervision. It
has been found that failure in the Healy tests or in the Porteous tests is more significant in this
respect than failure in the Binet Simon series. With a mental age above 10 evidence of defective
conduct or social maladaption is essential.
There is some difficulty in expressing the degree of defect in terms of years of retardation owing
to the greater import of a year's deficiency at the younger ages. To avoid this the quotient obtained
by dividing the assessed mental age by the chronological age or by 16 whichever be the lesser number
may be employed.

There is a certain degree of overlapping between the groups due to the fact that the decision
rests not only on estimates of mental age from actual examination but on attainments in reading,
writing and the like. So long as ability to read school books is a postulate for education in ordinary
elementary schools some provision for special or intermediate schools is needed for those who are unable
to learn to read or write, even though otherwise their general mental processes are but little retarded.
Over the age of 14 it has been the practice, in London, to regard a child who showed a mental
age of 10 or upwards combined with attainments equal to standard II. and some evidence of fitness
for employment or of ability for self protection in the world as being no longer certifiable.
When the time comes for leaving a special school cases are re-assessed. Stress is no longer laid
on the specialised educational abilities, but rather on the question of employability and self protection,
so that although a child might be regarded as defective in the sense of the Education Acts, in that he
needed a special variety of education, he would not be regarded as defective at 16 in the sense of the
Mental Deficiency Act, unless there was definite evidence that he was in need of care, supervision and
control for his own protection.
Dr. Boome has inquired into the use of simple tests of recognition of absurdities in the detection
of backward children in Cork-street (S.) School. He contrasted 25 children aged 2-14 years in a
special backward class with 38 normal children aged 11. The absurdity, viz., A soldier wrote home to
his mother as follows:—"Dear mother,—I am writing these few lines to you with a pistol in one hand
and a sword in the other," was read out to the children by the teacher and the number of readings
required before the point was detected noted.
Normal class.
Special backward class.
Detected absurdity at first reading 17 10
Detected absurdity at second reading 14 5
Detected absurdity at third reading — 2
Detected absurdity at fourth reading — 1
Failed altogether to detect absurdity 7 7
Mr. Bishop Harman gave evidence before the Committee enquiring into the causes of blindness
in children and a complete report of the evidence will be found in the official documents issued by the
Government. The following data are taken from the evidence.
Tests for
backward
children.
Causes of
blindness.