xxix.] EXCEPTIONAL PHENOMENA. 671 



perceived. The electric telegraph was a visionary dream 

 among mediaeval physicists ; l it has hardly yet ceased to 

 excite our wonder; to our descendants centuries hence 

 it will probably appear inferior in ingenuity to some 

 inventions which they will possess. Now every strange 

 phenomenon may be a secret spring which, if rightly 

 touched, will open the door to new chambers in the palace 

 of nature. To refuse to believe in the occurrence of any- 

 thing strange would be to neglect the most precious chances 

 of discovery. We may say with Hooke, that " the believing 

 strange things possible may perhaps be an occasion of taking 

 notice of such things as another would pass by without 

 regard as useless." We are not, therefore, to shut our ears 

 even to such apparently absurd stories as those concerning 

 second-sight, clairvoyance, animal magnetism, ode force, 

 table-turning, or any of the popular delusions which from 

 time to time are current. The facts recorded concerning 

 these matters are facts in some sense or other, arid they 

 demand explanation, either as new natural phenomena, or 

 as the results of credulity and imposture. Most of the 

 .supposed phenomena referred to have been, or by careful 

 investigation would doubtless be, referred to the latter 

 head, and the absence of scientific ability in many of 

 those who describe them is sufficient to cast a doubt upon 

 their value. 



It is to be remembered that according to the principle 

 of the inverse method of probability, the probability 

 of any hypothetical explanation is affected by the pro- 

 bability of each other possible explanation. If no other 

 reasonable explanation could be suggested, we should be 

 forced to look upon spiritualist manifestations as indicating 

 mysterious causes. But as soon as it is shown that fraud 

 has been committed in several important cases, and that in 

 other cases persons in a credulous and excited state of mind 

 have deceived themselves, the probability becomes very con- 

 siderable that similar explanations may apply to most like 

 manifestations. The performances of conjurors sufficiently 

 prove that it requires no very great skill to perform tricks 

 the modus operandi of which shall entirely escape the 



1 Jevons, Proceedings of the Manchester Literary and Philosophical 

 Society, 6th March, 1877, vol. xvi. p. 164. See also Mr. W. E. 

 A. Axon's note on the same subject, ibid. p. 166. 



