70 Wisconsin Academy of Sciences, Arts, and Letters. 



(5) A new fact presented to our senses, or duly vouched for, if 

 not explicable by known laws, is not to be rejected. It ma}' 

 hastily be assumed to contradict a law or the order of nature, 

 when, in truth, it is merely incapable of being referred to any 

 known combination of forces. The facts related in connection 

 with what is called " spiritualism," if they were duly attested, 

 would furnish a very striking illustration of this scientific principle. 



Contradiction properly applies to universal principles of reason, 

 not to lirnited empirical rules which may be, and which are, con- 

 travened by others. A cause operating with no effect is a contra- 

 diction in thought and in words. So is an effect without any 

 adequate cause. But the contradiction is not empirical ; for in 

 experience we see apparent failure, and similar effects fol- 

 lowing upon various antecedents. 



(6) I assume, also, as a postulate the existence of spiritual 

 substances, human and superhuman, which are capable oi modi- 

 fying material phenomena, through combinations of what are called 

 material forces (whatever these may be), if not otherwise. (It is 

 possible, indeed, that that purely metaphysical notion called 

 " force,"' is the sensible operation of that unknown substance 

 called "spirit.") 



Natural science may say that the existence of spiritual beings 

 is not proved, not even the existence of spiritual substance called 

 ego in man. But neither is their existence disproved, nor can it be. 

 The utmost that positivism can assert, is that their existence is 

 beyond the reach of investigation and knowledge. But since 

 this postulate is not unscientific, contradicts ko known principle 

 of nature and reason, and simply begs the existence of such beings 

 without a knowledge of their nature, which latter is what positiv- 

 ists dispute, I have a right lo employ it as a hypothesis, and this 

 is all that I require, in proving that wonders in ancient or modern 

 times are not antecedently incredible, nor to be rejected as con- 

 tradicting what we know.' 



' But I ought to add that this postulate of a free spirit implies that its 

 actions and its laws, even if they can be emperically known, do not strictly 

 come under the province of scientific phenomenal induction, where all 

 seems to be necessitated, and every antecedent to have its invariable conse- 



