SCIENCE AND REVOLUTION 



of understanding which will follow the human 

 mind, and which will, of course, be as much a 

 part of nature as we are, will gradually diminish 

 the difference between the absolutely unknowable 

 and the relatively knowable. Mathematically 

 speaking, the absolutely unknowable will be- 

 come infinitely smaller, the relatively knowable 

 will become infinitely greater, until the lines be- 

 tween the unknowable and the knowable become 

 imperceptible. 



This conception does not leave the least room 

 for any metaphysical explanation of anything 

 that we may not know. It leaves no room for 

 any supernatural ghosts or " spirits." 



That which theologians conceitedly call their 

 " spiritual " experience, and which according to 

 them no " atheist " can have, is a mixture of 

 vague feeling and self-suggestion. They sug- 

 gest to themselves that their indistinct, and to 

 them supernaturally mysterious, feeling of the 

 infinity of the natural universe is a " divine 

 revelation," and then they claim to have received 

 it by supernatural agencies. And when they are 

 shaken out of their self-hypnotism and asked to 

 show proofs for their assertions, they retire 

 gracefully behind that other bare assertion, that 

 this cannot be proven by any process of reason- 



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