GROUNDS OF DISBELIEF. 169 



for instance, are said, by persons studious of accuracy in ex- 

 pression, to be impossible in the circumstances of the case ; or 

 impossible unless some cause had existed which did not exist 

 in the particular case.* Of no assertion, not in contradiction 

 to some of these very general laws, will more than improba- 

 bility be asserted by any cautious person ; and improbability 

 not of the highest degree, unless the time and place in which 

 the fact is said to have occurred, render it almost certain that 

 the anomaly, if real, could not have been overlooked by other 

 observers. Suspension of judgment is in all other cases the 

 resource of the judicious inquirer ; provided the testimony in 

 favour of the anomaly presents, when well sifted, no suspicious 

 circumstances. 



But the testimony is scarcely ever found to stand that test, 

 in cases in which the anomaly is not real. In the instances 

 on record in which a great number of witnesses, of good repu- 

 tation and scientific acquirements, have testified to the truth 

 of something which has turned out untrue, there have almost 

 always been circumstances which, to a keen observer who had 

 taken due pains to sift the matter, would have rendered the 

 testimony untrustworthy. There have generally been means 

 of accounting for the impression on the senses or minds of the 

 alleged percipients, by fallacious appearances ; or some epidemic 

 delusion, propagated by the contagious influence of popular 

 feeling, has been concerned in the case ; or some strong 



* A writer to whom I have several times referred, gives as the definition of 

 an impossibility, that which there exists in the world no cause adequate to pro- 

 duce. This definition does not take in such impossibilities as these that two 

 and two should make five ; that two straight lines should inclose a space ; or 

 that anything should begin to exist without a cause. I can think of no defini- 

 tion of impossibility comprehensive enough to include all its varieties, except 

 the one which I have given : viz. An impossibility is that, the truth of which 

 would conflict with a complete induction, that is, with the most conclusive evi- 

 dence which we possess of universal truth. 



As to the reputed impossibilities which rest on no other grounds than our 

 ignorance of any cause capable of producing the supposed effects ; very few of 

 them are certainly impossible, or permanently incredible. The facts of travelling 

 seventy miles an hour, painless surgical operations, and conversing by instan- 

 taneous signals between London and New York, held a high place, not many 

 years ago, among such impossibilities. 



