336 Fallacies. [CHAP. xiv. 



extraordinary, we shall often find that he is not merely 

 thinking of the improbability of his guess being right, or of 

 the report being true, but, that along with this, he is intro 

 ducing the question of the throw having been produced by 

 fair dice. There is, of course, no reason whatever why such 

 a question as this should not also be referred to Probability,, 

 provided always that we could find the appropriate statistics 

 by which to judge. These statistics would be composed, not 

 of throws of the particular dice, nor of reports of the parti 

 cular witness, but of the occasions on which such a throw as. 

 the one in question respectively had, and had not, been 

 produced fairly. The objection to entering upon this view 

 of the question would be that no such statistics are obtain 

 able, and that if they were, we should prefer to form our 

 opinion (on principles to be described in Chapter XVI.) from 

 the special circumstances of the case rather than from an 

 appeal to the average. 



7. The reader will easily be able to supply examples, 

 in illustration of the distinctions just given ; we will briefly 

 examine but one. I hide a banknote in a certain book in a 

 large library, and leave the room. A person tells me that^ 

 after I went out, a stranger came in, walked straight up to 

 that particular book, and took it away with him. Many 

 people on hearing this account would reply, How extremely 

 improbable ! On analysing the phrase, I think we shall 

 find that certainly two, and possibly all three, of the above 

 meanings might be involved in this exclamation. (1) What 

 may be meant is this, Assuming that the report is true, 

 and the stranger innocent, a rare event has occurred. Many 

 books might have been thus taken without that particular 

 one being selected. I should not therefore have expected 

 the event, and when it has happened I am surprised. Now 

 a man has a perfect right to be surprised, but he has no 



