DISCUSSION.

The PRESIDENT said that in new investigations of this kind it was the first step that was the most difficult to make. It was very satisfactory that this first step had been made by a person so singularly well qualified as Mrs. Bryant, who, as was well known, had gained one of those rarely earned and highly prized degrees of Doctor of Science at the London University, on the ground of her proficiency in mental science. Mrs. Bryant also had large experience in practical education. We could therefore be sure that a person who had the precise gifts needed to carrying on these investigations successfully would make sure advance. He was an optimist in respect to this inquiry, seeing that much had been. really accomplished, and that we could hardly stand still, but must advance, and he did not see any boundary that certainly would limit that advance.

Mr. SULLY thought Mrs. Bryant's paper extremely suggestive. He had little to offer in the way of criticism, but would confine himself to throwing out one or two ideas that had occurred to him in listening to the paper. He was particularly struck with the way in which Mrs. Bryant had been able to distinguish between the two factors in observation, seeing what is directly present to the eye and interpreting what is seen. He thought her experiment might appropriately be followed by others specially designed to test each of these factors separately. Thus, the strictly visual capacity might be investigated by presenting objects having the minimum of suggestiveness, that is to say, perfectly definite but unerring forms, such as could be constructed by an arbitrary arrangement of lines. This would test the power of seeing finely, accurately, and rapidly. The other, or interpretative factor, would perhaps be best estimated by sketchy drawings of the human figure, landscape, and so forth, where just enough of concrete form is present to excite the imagination, and at the same time to offer unlimited scope for a varied constructive activity. Such an experiment would serve to bring to light the difference in children's power of taking sense hints, as they might be called, or of creating whole objects, or scenes, out of the scantiest data of sense impressions.

Mr. F. STORR welcomed Mrs. Bryant's paper as a sign that practical teachers were not only aware that psychology was an essential part of their training, but also beginning to co-operate with psychologists, and furnish them with observations on which to build. He criticised Mrs. Bryant's experiment as too ambitious, attempting, as it did, to test at once the powers of observation, retentiveness, and imagination. He referred to certain tests proposed by Mr. C. H. Lake, the first Secretary of the Education Society, by which it was attempted to determine quantitively at any given time a child's faculties, as distinguished from knowledge and method, which are gauged by ordinary examinations. He called on Mr. Sully and other psychologists present to set school

masters definite work of this kind, and promised, as a schoolmaster, to do the best to carry out their instructions.

Mr. CARVETH READ expressed his appreciation of Mrs. Bryant's paper, both for its general conception and the method of marking it out. He would only suggest that the scheme of such experiments might be extended by keeping a record of the mental characteristics of children at different ages, and especially of the same children year by year. We might then learn at what ages, on the average, different faculties of observation, imagination, reasoning, became conspicuous, and in what degrees and proportions, and so regulate education as to begin the training of these faculties severally at the most favourable times. It would also be interesting to know whether the same general mental character persisted from year to year, or changed; in what proportion of cases early mental promise was fulfilled; at what ages changes of mental balance were to be looked for. If the studies preferred by children excelling in certain faculties were recorded, we might perhaps infer that such studies were fitted to train those faculties.

The following paper was then read by the author:

The COMPARATIVE DISTRIBUTION of JEWISH ABILITY.1

By JOSEPH JACOBS, Esq., B.A.

[WITH PLATE XV.]

In a previous communication to this Institute I laid before it all the information I could collect as to the racial characteristics of modern Jews, their vital statistics, and bodily measurements. At the same time I expressed my belief that it would be possible to estimate with some degree of precision their intellectual ability as compared with that of other Europeans, and I promised to give this comparison on some future occasion. I shall endeavour to redeem that promise in the following pages. In doing so I find myself in face of two difficulties. The first was to discover a method of measuring ability. The heights of Jews can be calculated easily enough, their vital statistics need only to be collected from the bureaux of Europe. But who shall measure a man's mind so as to compare it with that of others? It was necessary to find some method that would give definite

1 Parts of this paper were read before the Aberdeen Meeting of the British Association.

2.46 'Journ. Anthrop. Inst.," August, 1885.

results and should have at the same time some claims to scientific accuracy and trustworthiness. Fortunately for me such a method has been before the world for the last sixteen years in Mr. Galton's "Hereditary Genius," and what I shall do in this investigation is only to apply to Jews the same line of argument that he applied to Englishmen in that well-known book. But having found my method, there still remains the second difficulty of explaining it in such a way that it will not be too wearisomely arithmetical. Roughly speaking, the method consists in finding how many eminent men of certain rank exist in each million of Englishmen and of Jews. To do this it is impossible to avoid numerical details, and I fear I must force the reader to pass some time in the uncongenial company of the Rule of Three. Luckily, however, the method likewise admits of being exhibited in a graphic form, and I hope to render it intelligible by means of a couple of diagrams, and by drawing upon the reader's imagination to make two tolerably simple suppositions.

The first is this. Suppose we ordered a tailor to cut out a piece of cloth under the conditions that it should be-(1) of fixed breadth; (2) contain a fixed area; (3) be symmetrical about a central axis; and (4) have no indentations in it. He would soon find that the first snip of the scissors would determine the shape of the cloth. For if (as in the dotted lines of fig. 1, Plate XV) he began to cut within the pattern curve he would have to bring the outline outside it, in order to make up the given area, and if he began outside it he would have to bring the apex within for the same reason. Bearing this sartorial experience in mind we may turn to our second stretch of imagination. I have said that our method consists in estimating the number of eminent men among a million Englishmen or Jews, as the case may be. Suppose that we had these million men collected together on Salisbury Plain, and suppose further that we were gifted with the insight of a recording angel and could arrange them in sixteen classes according to their ability, ranging from the greatest genius among them to the most degraded idiot. A long wall with fifteen projecting walls perpendicular to it would give us, as it were, sixteen pens, in which we could place our various classes. It is obvious that the central or mediocre classes would contain far more than the extremes: geniuses and, luckily too, idiots are far more rare than mediocrities. As a matter of fact, on the hypothesis here employed of the distribution of ability according to the law of deviation from the average, the two central classes would stretch out a broad mass of humanity nearly twice as long as the base line. If now we built a wall round our million men thus classified this would describe a curve

resembling in shape a section of a penny trumpet.1 But this curve is of the same kind as we previously requested our tailor to cut out for us; it is of fixed breadth, symmetrical round the central axis, of fixed area, that filled by a million men, and it has no indentations, for there cannot be a larger number of men in a class more remote from mediocrity than in one nearer. But if this is so, we know from our former supposition that after a small portion of the boundary wall at the extremity had been built the shape of the remainder would be determined, so that all that would be necessary would be to find the number of men forming the first three or four classes and build the wall enclosing them. Mr. Galton built that wall for Englishmen, if I may say so, in his book "Hereditary Genius," and I have endeavoured to do the same for Jews and incidentally for Scotchmen, with results roughly indicated in fig. 2. This has been drawn out of scale at the extremities for the sake of clearness, and only gives approximately the true shape of the curve of distribution of ability on Mr. Galton's hypothesis, that talent is distributed round an average mediocity like shots are distributed round the bull's-eye of a target ("Hereditary Genius," pp. 30-34). With this explanation I turn to the calculations, which enable us, however roughly, to estimate the comparative distribution of ability among Englishmen, Scotchmen, and Jews.

But first we must recall the estimate by which Mr. Galton was enabled to determine the distribution of English ability. As will be remembered, he estimated that of every million Englishmen over fifty, 425 obtained sufficient reputation to earn them a place in Cooper's "Men of the Time," and of these 425 there would be 250 of equal or superior ability to that of an English judge. Assuming then that the exponential law of error applied to the distribution of talent he was enabled to subdivide these 250 into three classes, equally removed from one another. The first class (termed Class X) was composed of only one individual, whose prominence may be conceived from the fact that only 9 of this class are living at one time in the United Kingdom, only 2 among Englishmen over fifty. The next class, G, would include 14 members in each million, or 111 of all ages in the British Isles, while the third class, F, would average 233 per million; so that these islands would have 1,863 individuals of this class, but only 468 over fifty, before which age, as a rule, men do not obtain fame. These results, while enabling us to render more

the law of deviation from the average. Cf. Quetelet, "Letters on Probabilities;" Venn, "Logic of Chance."

2 For explanation of Plate see p. 378.