LIFE AND THE COSMOS 289 



a different matter from proving it to be the 

 only force which directs evolution. An early 

 eulogy by Du Bois-Reymond upon the work 

 of Darwin clearly discloses the nature of the 

 situation: "Here is the knot, here the great 

 difficulty that tortures the intellect which 

 would understand the world. Whoever does 

 not place all activity wholesale under the sway 

 of Epicurean chance, whoever gives only his 

 little finger to teleology, will inevitably arrive 

 at Paley's discarded 'Natural Theology,' and 

 so much the more necessarily, the more 

 clearly he thinks and the more independent 

 his judgment . . . the physiologist may define 

 his science as a doctrine of the changes which 

 take place in organisms from internal causes. 

 . . . No sooner has he, so to speak, turned 

 his back on himself than he discovers himself 

 talking again of functions, performances, ac- 

 tions, and purposes of the organs. The possi- 

 bility, ever so distant, of banishing from na- 

 ture its seeming purpose, and putting a blind 

 necessity everywhere in the place of final 

 causes, appears, therefore, as one of the 

 greatest advances in the world of thought, 

 from which a new era will be dated in the 

 treatment of these problems. To have some- 

 what eased the torture of the intellect which 

 ponders over the world-problem will, as long 



