Principles of western civilisation

46 WESTERN CIVILISATION CHAP.

irreconcilable with either. It was perfectly true that there were large animals endowed with great longevity ; but so also, and to an equal extent, were many small animals. Similarly, inertness of habit might appear to be correlated with length of life; but, on the other hand, some of the most marked instances of extraordinary longevity were to be found amongst a class of animals where the vital processes take place with the greatest rapidity, namely, the birds ; this class also, on the whole, surpassing even the mammalia in average duration of life.’

There was one fact, however, which was held to stand out clearly. It was that Natural Selection must in any case have tended to procure the greatest possible advantage, and the highest possible degree of self-vealisation, for the individual in the actual conditions of its existence. Mr. Spencer had indeed developed this view in his theory of human society, where he regarded the significance of the culmination of life in the social state as consisting largely in the fact that therein, at last, the lives, not only of each but of all, tended to be “the greatest possible alike in length and breadth.” ”

The deep impression produced by Professor Weismann’s paper may be at once understood when it is said that the author not only challenged the assumption underlying all this series of prevailing opinions, but boldly advanced to the remarkable conclusions : (1) that the duration of life in the individual was not primarily due to external physical conditions, nor to molecular causes inherent in organic nature *;

1 Cf. Essays upon Heredity, vol. i., by August Weismann ; Zhe Duration of Life, trs. by A. E. Shipley. 2 The Principles of Ethies, § 48. 3 Essays upon Heredity, vol. i.; The Duration of Life, p. 24.