BIOLOGY AND SOCIOLOGY 81 



consequently his adult self, the end-product of that 

 development, can be altered far more rapidly than 

 in any other organism. Finally, it is possible, as is 

 being increasingly realized, thus to accumulate expe- 

 rience relating to the alteration of biological inher- 

 itance, and so eventually to substitute conscious 

 purpose for blind natural selection in man's future 

 evolution. 



Next point: by means of speech, tradition, and 

 invention, man has been enabled to extend his bio- 

 logical environment — in other words, that part of the 

 cosmos with which he stands in relation — till it has 

 reached an enormously greater size than that of any 

 other organism. He is learning ever more facts about 

 the celestial bodies, studying stars that are at an in- 

 conceivable distance from him. He is able to travel 

 at will to all parts of the globe. He can penetrate 

 by means of tradition to remote periods of the past : 

 as Mr. Wells has forcibly put it, a modern English- 

 man can know more of the world in the Classical 

 Epoch than could the most learned Greek or Roman. 

 And even when he can no more get into contact with 

 ideas, he can still unravel facts: flint implements 

 help him to the history of man, fossils to that of life, 

 rocks to that of the globe, stars to that of the solar 

 system. In time, as well as in space, his environ- 

 ment enlarges to a size that is for practical purposes 

 infinite, whereas no other organism can penetrate be- 

 yond its own memories, or, at most, do more than 

 profit by those of the generation immediately before 



