4-28 PROGRESS OF SCIENCE IN THE CENTURY. 



sional exuberances of the arbor vita. Thus we have 

 Darwinian, Lamarckian, and Nagelian schools, and 

 various combinations of these up to complete eclecti- 

 cism. From this others have reacted to an agnostic 

 position, which in its more kinetic expression means 

 active scepticism, and this thdtige Skepsis seems to us 

 the more useful mood for present-day evolutionists. 

 SUMMARY. The evolution-idea is not only essen- 

 tially simple, but also very ancient. It is perhaps 

 as old as clear thinking, which we may date from 

 the (unknown) time when man discovered the year 

 with its marvellous object-lesson of recurrent se- 

 quences, and realised that his race had a history. 

 Whatever may have been its origin, the idea was 

 familiar to several of the ancient Greek philoso- 

 phers, as it was to Hume and to Kant; it fired the 

 imagination of Lucretius and linked him to another 

 poet of evolution Goethe; it persisted, like a latent 

 germ, through the centuries of other than scientific 

 prc-occupaiion ; it was made actual by the pioneers 

 of modJsrn biology men like Buffon, Lamarck, 

 Erasmus Darwin, and Treviranus; and it became 

 current intellectual coin when Darwin, Wallace, 

 Spencer, Haeckcl, and Huxley, with united but 

 varied achievements, won the conviction of the ma- 

 jority of thoughtful men. Since this achievement, 

 there has been a concentration of enquiry on the 

 originative and directive factors in the evolution- 

 process, but this enquiry is still young. 



THE PRESENT ASPECT OF THE EVOLUTION THEORY. 



'Attitude towards the General Idea of Evolution. 

 The appreciation of the general idea of evolution 

 has changed for the better since the early Darwinian 



