1 1 4 A Factor in Evolution 



for pathological cases show that unless some adequate 

 idea of a former movement made by the same muscles, 

 or by association some other idea which stands for it, 

 can be brought up in mind, the intelligence is helpless. 

 Not only can it not make new movements ; it cannot 

 even repeat old habitual movements. So we may say 

 that intelligent adjustment does not create coordinations; 

 it only makes functional use of coordinations which are 

 alternatively present already in the creature's equipment. 

 Interpreting this in terms of congenital variations, we 

 may say that the variations which the intelligence uses 

 are alternative loossibilities of muscular movement ' (from 

 an earlier page). The only possible way that a really new 

 movement can be made is by making the movements already 

 possible so excessively a7id with so many vaiieties of com- 

 bination, etc., that new adjustments are liable to occur. 



5. The problem seems to duplicate in the main the con- 

 ditions which led to the formulation of the principle of natu- 

 ral selection. The alternatives seemed to be 'pure chance ' 

 or * special creation.' The law of * overproduction with sur- 

 vival of the fittest ' came as the solution. So in this case. 

 Let us take an example. Every child has to learn how to 

 write. If he depended upon chance movements of his 

 hands, he would never learn how to write. But on the 

 other hand, he cannot write simply by willing to do so ; he 

 might will forever without effecting a 'special creation' 

 of muscular movements. What he actually does is to use 

 his hand in a great niany possible zvays as near as he can 

 to the way required ; and from these excessively produced 

 movements, and after excessively varied and numerous 

 trials, he gradually selects and fixes the slight successes 

 made in the direction of correct writing. It is a long and 



