6o8 



NATURE 



October 22. 1903 



lations. Suppose, then, we assume that the moral and 

 mental qualities in man, like the physical, follow a normal 

 law of distribution. What results shall we obtain by thus 

 assuming perfect continuity between the physical and 

 psychical? I cannot free myself from the conception that 

 underlying every psychical state there is a physical state. 

 Hence I put to myself the problem as follows : — 



Assume the fundamental laws of distribution which we 

 know hold for the physical characters in man, and see 

 whither they lead us when applied to the psychical 

 characters. They must (a) give us totally discordant results. 

 If so, we shall conclude that they have no application to the 

 mental and moral attributes. Or (6) they must give us 

 accordant results. If so, we may go a stage further, and 

 ask how these results compare with those for the inheritance 

 of the physical characters ; are they more or less or equally 

 subject to the influence of environment? Here are the 

 questions before us. Let us examine how they are to be 

 answered. Taking as an example ability in girls, we find 

 that the resemblance between sisters is 0.47. There can, I 

 think, be no doubt that intelligence or ability follows pre- 

 cisely the same laws of inheritance as cephalic index or any 

 other physical character. 



I ask you to admit that I came to this inquiry without 

 prejudice. I expected a priori to find that the home 

 environment largely affected the resemblance in moral quali- 

 ties of brothers and sisters. Putting any thought of pre- 

 judice on one side, accept for a moment the methods 

 adopted, and look at the broad results of the inquiry. You 

 have in the first table the mean resemblance of the physical 

 characters of brothers and sisters from my records of 

 family measurements. You have in the second table the 

 mean of the physical measurements of our school records. 

 These two series absolutely confirm each other, and give a 

 mean resemblance of 0.5 nearly between children of the 

 same parents for all physical characters. How much of 

 that physical resemblance is due to home environment ? 

 You might at once assert that size of head and size of body 

 are influenced by food and exercise.- It is quite true. But 

 can any possible home influence affect cephalic index or 

 eye colour? I fancy not; and yet these characters are 

 within broad lines inherited exactly like the qualities 

 directly capable of being influenced by nurture and 

 exercise. I am compelled to conclude that the environment 

 influence on physical characters is to the first approxim- 

 ation not a great disturbing factor when we consider degrees 

 of fraternal resemblance in man. 



Now turn to the list of the degrees of resemblance in the 

 mental and moral characters. We find, perhaps, slightly 

 more irregularity than in the case of the physical characters. 

 The judgment required is much finer, the classification 

 much rougher, but the obvious conclusion is still that the 

 values of the coefficient a giving the resemblance again 

 cluster round 05. 



We are forced, I think literally forced, to the general 

 conclusion that the physical and psychical characters in 

 man are inherited within broad lines in the same manner 

 and with the same intensity. 



This sameness surely involves something additional. 

 It involves a like heritage from parents. So we inherit our 

 parents' tempers, our parents' conscientiousness, shyness 

 and ability, even as we inherit their stature, forearm and 

 span. 



At what rate is that? [A table was shown which repre- 

 sents our present knowledge of parental inheritance in man 

 and in the lower forms of life, the resemblance of parent 

 and offspring being again roughly 05.] So the psychical 

 characters are not features which differentiate man from the 

 lower types of life. 



If the conclusion we have reached to-night be substantially 

 a true one, and for my part I cannot for a moment doubt 

 that it is so, then what is its lesson for us as a community? 

 Why, simply that geniality and probity and ability, though 

 they may be fostered by home environment and good 

 schools, are nevertheless bred and not created. The educa- 

 tion is of small value unless it be applied to an intelligent 

 race of men. 



Our traders tell us we are no match for the Germans or 

 Americans. Our politicians catch the general apprehension 

 and rush to heroic remedies. Looking round impassion- 

 ately from the calm atmosphere of anthropology, I fear 



NO. 1773, VOL 68] 



there really does exist a lack of leaders of the highest 

 intelligence, in science, in the arts, in trade, even in politics. 

 I do seem to see a want of intelligence in the British 

 professional man and in the British workman. But I do 

 not think the remedy lies in adopting foreign methods of 

 instruction or in the spread of technical education. I 

 believe we have a paucity just now of the better in- 

 telligences to guide us, and of the moderate intelligences 

 to be guided. The only account we can give of this on 

 the basis of the result we have reached to-night is that we 

 are ceasing as a nation to breed intelligence as we did 

 fifty to a hundred years ago. The only remedy, if one be 

 possible at all, is to alter the relative fertility of the good 

 and bad stocks in the community. We stand, I venture 

 to think, at the commencement of an epoch which will be 

 marked by a great dearth of ability. We have failed to 

 realise that the psychical characters which are in the modern 

 struggle of nations the backbone of a State are not manu- 

 factured by home and school and college ; they are bred in 

 the bone ; and for the last forty years the intellectual classes 

 of the nation, enervated by wealth or by love of pleasure, or 

 following an erroneous standard of life, have ceased to give 

 us the men we want to carry on the ever-growing work of 

 our Empire, to battle in the fore rank of the ever-intensified 

 struggle of nations. 



The remedy lies in first getting the intellectual section 

 of our nation to realise that intelligence can be aided and 

 be trained, but no training or education can create it. You 

 must breed it ; that is the broad result for statecraft which 

 flows from the equality in inheritance of the psychical and 

 the physical characters. 



THE APPLICATION OF LOW TEMPERATURES 

 TO THE STUDY OF BIOLOGICAL PROBLEMS} 

 "T^HE cellular doctrine lies at the basis of modern bio- 

 •*■ logical research. Living matter in its simple and 

 complex conditions consists essentially of protoplasm with 

 a contained body or nucleus. The two elements plasma and 

 nucleus constitute the elementary organism — the cell. The 

 lowest individual forms of life are represented by a single 

 cell, and such unicellular organisms may be either of a 

 vegetable or animal type. The cells in each instance exist 

 as free living and independent organisms. The higher 

 forms of life are built up of parts in which the structural 

 unit remains the cell, despite the modifications the cell 

 necessarily undergoes as a fixed element in the various 

 tissues and organs. All phases of animal and plant life 

 are demonstrably of cellular origin and organisation, and 

 their vital manifestations represent the summed up activi- 

 ties of cells. Every vital problem, therefore, is ultimately 

 a cellular problem, and a direct study of the cell, in so 

 far as may be possible, is the keynote of biological re- 

 search. The methods to be adopted will depend upon the 

 problem it is desired to investigate. A histological 

 technique, aided by the microscope, will naturally be em- 

 ployed where it is desired to study the relations of parts 

 and the structural organisation of the tissues and their 

 cellular elements. The soluble products of the living cell 

 spontaneously present themselves for examination by 

 chemical and other means. It is otherwise with regard to 

 the agencies acting and the processes occurring within the 

 confines of the cell. These are naturally beyond the range 

 of the ordinary methods of observation. The essential 

 processes of life are intracellular and intimately bound up 

 with the living substance of the cell, and of these but few 

 data are possessed. The importance of the problems in- 

 volved is as great as their investigation is difficult. The 

 cell exercises its vital functions in virtue of a specific 

 physical and chemical organisation of its molecular con- 

 stituents. The ordinary methods of biological and chemical 

 research modify or destroy this organisation, and do not 

 admit of an intimate study of the normal cell constituents. 

 For this purpose it is essential to eliminate or to reduce 

 to a minimum the influence of external modifying agents 

 on the cell or its immediate products. An intracellular 

 physiology can only be based on a direct study of intra- 

 cellular constituents apart from their secretions and pro- 

 ducts. This, in ordinary circumstances, is impossible with 



1 By Dr. Allan Macfadyen. Communicated to Section B of the British 

 Association at Southport, by Prof. J. Dewar, F.R S. 



