568 LIFE : OUTLINES OF GENERAL BIOLOGY 



as more unstable. Man is perhaps more given to experiment both 

 with his body and his mind, and with other people. In this connec- 

 tion we notice that there is among men a greater frequency of genius, 

 insanity, idiocy, crime, and many kinds of anomalies. Stammering 

 is much less frequent among females. 



The physiologists tell us that man uses more oxygen and more 

 combustible material, and has more waste in consequence. Man's 

 blood has a higher specific gravity, more red blood corpuscles, more 

 haemoglobin. In short, man is the relatively more active or katabolic 

 type. 



Of some significance, again, is the relatively great tenacity of life 

 in women. They are longer-lived. Alike in infancy and in old age 

 they show a greater power of resisting death. Indeed, at every age, 

 except 15 to 20, their tenacity of life is greater than man's. Their 

 constitution has staying qualities, probably wrapped up with 

 femaleness. 



We have said enough to illustrate the detailed differences between 

 man and woman, but we must briefly allude to three general im- 

 pressions which we gain from the inquiry. The first is that the 

 differences are correlated; they hang together, they are outcrops 

 of the deep fundamental distinction. We may say that the tenacity 

 of life, the longer life, the characteristic endurance, the greater 

 resistance to disease, the smaller percentage of genius, insanity, 

 idiocy, suicide, and crime, and so on, are all correlated with the 

 distinctively female constitution, which may be theoretically 

 regarded as relatively more constructive in its metabolism. 



This correlation of differences includes the mental as well as the 

 bodily, for it is impossible to separate them. We may assert this on 

 general grounds which lead us to recognise the unity of the organism; 

 but it can also be proved, in indirect ways at least. Thus Karl 

 Pearson has shown that the inheritance of well-defined psychical 

 characters can be formulated like that of physical characters. "We 

 inherit our parents' tempers, our parents' conscientiousness, shy- 

 ness, and ability, as we inherit their stature, forearm, and span." 

 The psychical characters are inherited in the same way, and at the 

 same rate as the physical. 



To be carefully guarded against is the temptation to sum up the 

 contrast of the sexes in epigrams. Personally we regard woman as 

 the relatively more anabolic organism, man as the relatively 

 more katabolic; and whether this biological hypothesis is or is not 

 soimd, it certainly does no social harm. But when investigators say 

 that woman is more infantile and man more senile; that woman is 

 "undcveloixjd man", and man an evolved woman, we get among 

 generalisations not only extreme but practically dangerous. Not 

 least dangerous of these generalisations is one of the most familiar 

 that man is more variable than woman, that the raw materials of 



