644 



NATURE 



[January 13, 192 1 



round with the souls of healthy boys and girls it is 

 a different matter, and teachers have no more right 

 to experiment upon them in psychical matters than 

 to make them the vile body for testing the properties 

 of a patent nostrum. It may be true, as Dr. Crichton 

 Miller has pointed out, that in nineteen out of twenty 

 cases examined by the expert analysts the results 

 point to faulty upbringing, either at home or at school, 

 but it must be borne in mind that these twenty cases 

 are not normal or typical in any way. When Dr. 

 Mary Bell says there is no sin in a child helping itself 

 to the contents of the mother's purse in order to buy 

 presents for a teacher, this is simply playing fast and 

 loose with the distinctions between right and wrong. 

 Most homes and most schools will be well advised to 

 stick to the Ten Commandments. If a child gets into 

 serious trouble or 'is not healthily happy, there is a 

 clear case for psychotherapy. Every schoolmaster of 

 experience "knows how helpful it may be in sug- 

 gesting a hopeful method of treatment, for 

 there were cases of shell-shock among children 

 in the raid areas as well as among soldiers 

 at the Front ; and so long as boys are boys there 

 will be cases of practical jokes, such as those which 

 drove the poet Gray out of Peterhouse at Cambridge, 

 and there will be cases of bullying, though these are 

 now, happily, very rare. But for the normal treat- 

 ment of normal school-life, the best training of the 

 unconscious life, as Mr. Talbot said, is through the 

 school games, school camps, scouting, and everything 

 which enables a child's psychical faculties to function 

 freely in relationship both to his teachers and to his 

 fellows. Inasmuch as every child does not find itself 

 in cricket, football, and hockey, it is well to widen 

 the field of opportunity and to offer as large a variety 

 as possible, so that no child in any school may live 

 such a cowed life as Cowper lived at Westminster. 



Prof. Percy Nunn's address on testing intelligence 

 was as full of humour as of practical help and sug- 

 gestion. Clearly the secondary school needs a certain 

 quantum suff. of knowledge as well as of intelligence, 

 and therefore written examination cannot be super- 

 seded in the selection of free-place holders. Both 

 these forms of test bring out the child that has the 

 power of rapid mental mobilisation, and the ablest 

 child of all may very likely fail to shine. " Senti- 

 mental Tommy " failed to win his place on the list 

 because he spent half the time available in thinking 

 out the exact word which he wanted to fit his thought. 

 Clearly the consummate artist in words is not a suc- 

 cessful examinee. There is, in addition, the child 

 who thinks below the surface of things, whom psycho^ 

 logists call the "introvert." He will take the question 

 prof>osed and look at it in its bearings in relation to 

 other deep thoughts which occupy his mind, and, as 

 likely as not, he will w'ant to reformulate the ques- 

 tion altogether before he sets himself to answer it. 

 As Prof. Nunn admitted, our present methods pass 

 over this child ; a Newton or a Coleridge would in all 

 probability fail to win a scholarship. This is one 

 point which calls for further work for the psycho- 

 logists. Profs. Terman and Thorndyke have not yet 

 faced this question, and the American Army had 

 probably no use for a Coleridge or other poetic soul. 

 This is only one of many questions which call for 

 further research. It is important to be able to 

 measure the vital force of the competitor, for a fund 

 of vitality is quite as important for effectiveness in 

 study, and, indeed, in life in general, as intelligence. 

 It would be interesting to know how much deep breath- 

 ing and cardiac strength have to do with that tenacity 

 of purpose which so often wins through to high 

 achievement, when mere brilliance of intellect fails 

 because it is not backed by strength of perseverance. 



The Mathematical Association. 



AT a crowded annual meeting on January 4, Prof. 

 A. S. Eddington gave an account of relativity. 

 Those who wish to inform themselves on this subject 

 will naturally go to Prof. Eddington 's attractive book, 

 "Space, Time, and Gravitation." No experiments 

 to determine the motion or whereabouts of the aether 

 had ever led to any but a negative result, as if one 

 solving an equation should end up with the dis- 

 appointing result = The view had therefore been 

 put forward that there were certain compensating 

 influences concealing the motion of the aether from de- 

 tection. But Einstein had dared to take up the atti- 

 tude of Betsey Prig in the matter of Mrs. Harris, " I 

 don't believe there's no sich a person!" The party 

 of Mrs. Harris, however, protested against being 

 called upon actually to produce her. 



Two points of pedagogic importance were made. 

 First, there is geometry- In Prof. Eddington's 

 opinion geometry is not the science of space relations 

 in an empty world, but the science of space relations 

 of material objects ; its fundamental assumptions are 

 to be ascertained by measurements made on such 

 objects. From this it would follow that the philo- 

 sophical way to begin the study of geometry is by 

 plaving with mathematical instruments and bits of 

 cardboard. This is what teachers have been dis- 

 covering, beginning at the other side of the problem — 

 beginning, that is, with the boy into whom they have 

 to insert learning. Prof. Eddington reaches the same 

 conclusion by considering the nature of the learning 

 that is to be inserted into the boy. So the two sets 



NO. 2672, VOL. 106] 



of workmen meet in the middle of the tunnel and 

 the line is clear for traffic. 



Secondly, there is dynamics. Consider the case of 

 a pendulum. On one side of the equations we have 

 been accustomed to write the forces, including gravity. 

 On the other we write inertia and acceleration, in- 

 cluding the acceleration towards the centre. But the 

 last term could algebraically be written on the force 

 side, with sign reversed ; it would be identified with 

 what has been known popularly as centrifugal force. 

 Teachers have generally been rather prudish about 

 this term, but Prof. Eddington assures us that centri- 

 fugal force and weight are equally real or unreal ; 

 it would appear, then, tliat they should be on the 

 same side of the equation. (But which side?) Simi- 

 larly, the passenger walking along the aisle of an 

 accelerating tube-carriage is justified in considering 

 himself in equilibrium under a pressure from the 

 floor and a gravitational force equally inclined 

 to the vertical ; and gravity is, in practice, not dis- 

 entangled from the centrifugal force of the earth's 

 rotation. 



Dr. Brodetsky followed with a paper proposing to 

 inject fresh blood into dynamics by using the aero- 

 plane. He explained that the problem could be so 

 simplified that, after a year's study of dynamics, the 

 student could work problems on the motion of aero- 

 planes, including climbing, vol plani, and banking. 

 We shall look forward to seeing these suggestions 

 worked out in detail in a forthcoming issue of the 

 Mathematical Gazette. 



