DB LA PERCEFFION .~ LA PENS]~..E 323

qui parait grandement facilit~e par une verbalisation int6rieure qui fait prendre conscience A l'enfant des 616merits du mod61e (nombre, forme, couleur, orientation r&iproque).

On constate donc entre ies groupes des diff6rences significatives suivant la nature des 6prcuves, qu'on peut ainsi classer comme tests de diff6renciation ent:e les enfants dont le langage n'est pas 6galement d6velop#.

Une v6ritable ~chelle d'intelligence non verbale qui ne d~savantagerait pas les enfants d6ficients du langage devrait donc se limiter A des tfiches sensori-motrices pure,.

Mais peut-on en 6tablir la gradation, hors des progr~s que ~ustement l'acquisition du langage rend possibles?

THE CONCEPT OF DIRECTION IN THINKING

BY

M. A. JEEVES

(University of Leeds)

It has often been pointed out that thinking has a strong directional character and this has in the past been a~ounted for in a variety of ways. A~ times, direction is conceived as a property of the stimulus problem materials, at other times it :~.s ~-.omething located in the organism solving the problem, and at other times it is seen as an interaction between these two.

Following a suggestion of B:trtlett's that it would be profitable to regard thinking as of the nature of a Mgh-level skill, a series of experiments have been designed and carried out, which make use of certain pointers available to us from the work already carried out on perceptuo-motor skills.

The experimental material in all cases consisted of serially related items of evidence, which were presented to the subjects of the experiments, to be continued to completion by a process of extrapolation or of interpola- tion. From the different experimental situations used there seemed to emerge certain ,.'ommon characteristics, which could be regarded as directional cues to be used by the subjects in their progression towards a satisfactory com- pletion of the incomplete evidence.

After discussing some of the characteristics, which, from the experiments, seemed to be common to the bodily and mental skills, the paper goes on to list the specific findings which relate to the "direction" of thought.

324 THEME 12

Those factors, which, from the ex,t~rimental investigations, are seen to influence the perception and udlisation of directional cues include the following: 1. the medium of presentation of the evidence; 2. the dimensionaiity of the evidence; 3. the degrees of freedom of the system; 4. the number of items of evidence initially available; 5. the, order of the items of evidence initially available; 6. the general nature of the task set.

These factors are discussed, along with the strategies of completion used by the subjects. It is further suggested how this may link up with one parti- cular characteristic of perceptuo-motor skills, namel:', the way in which the sequence of movements of a bodily skill, as it proceeds, tends to take on a characu.- of inevitability and of "directionality".

RESPONSES OF A GROUP OF MENTALLY SUBNORMAL AND

DEFECTIVE SUBJECTS TO PIAGET'S METHOD OF ANALYSING

THE DEVELOPMENT OF PRE-NUMBER CONCEPTS

BY

H. BLAIR HOOD

(Cumberland County Council, Great Britain)

In his book "La gen~se du Nombre chez l'Enfant", Piaget describes his genetic studies of the processes or logical operations which lead to tile understanding and intelligent use of numbers in early childhood. Thus he shows that there is a pre-logical stage when certain logical operations are not yet fully developed, which corresponds fo the pre-number stage, and during which, although a child may be able *o do simple number work if he is given plenty of methodical drill in Arith~etic, his comprehension of what he is doing is clearly limited. Most of the-~e logical operations run through three stages corresponding roughly to (I) complete absence of operation, (II) a transitional stage when the operation does not yet show definite and automatic response, and (III) the tirol ,~tage of full development when the response is immediate and certain. Piagd's research shows that on the average children tend to be at a certah~ age when they arrive at ea;'h of these stages. In this paper we shall deal primarily with a group of educationally subnormal boys, and also a number of ineducable O.e.