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J.—PSYCHOLOGY. 231 
old doctrine of native faculties is out of favour with the orthodox psycho- 
logist of to-day. We are told that there is no such thing as memory: 
there are only memories ; that there is no such thing as a general power 
of muscular skill: there are only separate motor habits, each inde- 
pendently learnt. Nevertheless, the very way in which such acquire- 
ments are limited, particularly among individuals who have had iden- 
tical opportunities at school and at home, argues an innate basis; and 
inquiries into heredity confirm the suspicion. On the existence and 
nature, therefore, of these hypothetical ‘ group-factors ’"—inborn powers 
that seem partly general but not entirely so, partly specific but not abso- 
lutely so—further research is imperatively needed. How far, for 
example, is there a group-factor underlying all kinds of memory, or all 
kinds of imagination, every form of mental quickness, every form of 
motor dexterity, and every form of apprehension through the several 
senses? Of the great difficulty of the problem, the prolonged work 
on mental imagery is an excellent example. The early experiments of 
Galton convinced contemporary psychologists that individuals might be 
classified into fairly definite types—the eye-minded, the ear-minded, 
the motor-minded, and so forth. That these sharp lines of demarcation 
can be no longer drawn has since been amply proved. But yet, in 
spite of countless inquiries, no satisfactory tests have been devised even 
for a capacity so clearly definable as visualisation; nor can we guess 
how far it may be specific, and how far it may be inborn, nor 
how far it is a manifestation of something more general, or how far it 
is simply a question-begging term for an aggregate of yet more limited 
habits or tendencies, each specific in itself.”* 
il. Acquired Attainments. 
I turn now from inborn abilities to those that are acquired. From 
a practical standpoint these may be broadly grouped into educational 
attainments and vocational attainments respectively. 
For the teacher one of the most helpful achievements of experimental 
psychology has been the recent elaboration of standardised scholastic 
tests. Simple foot-rules have been scientifically constructed for measur- 
ing a child’s knowledge of the chief school subjects—reading, spelling, 
arithmetic, handwriting, drawing, composition, and the like. By the 
help of such age-scales—those, for example, published by the London 
County Council—it is now practicable to assign, in the space of a few 
21 To hereditary differences of race, sex, and social class I have no space 
to allude. The main conclusion that can be drawn from experimental work is, 
I think, the following: Innate group-differences exist; but they are small. 
Training and tradition account for the more conspicuous. The inborn mental 
differences between class and class, between nation and nation, and between 
women and men, taken on the average and in the gross, are swamped by the far 
wider differences among the individual members that make up any single group. 
As to the mental differences between the two sexes—the topic upon which rather 
more experimental work has been done—the reader may be referred to the 
recent report of the Consultative Committee of the Board of Education on 
Sex-differences and the Secondary School Curriculum (H.M. Stationery Office, 
1922). 
