536 THE ROYAL SOCIETY OF CANADA 



from the nature of the case, it will be generally found, after close 

 examination, that practically as much can be said on either side of 

 any probable conclusion of the inferior form reached by balancing 

 of reasons pro and con. Any person with a tendency either for or 

 against the conclusion, can usually convince himself that there is 

 enough positive ground, or enough weakness in the opposing position, 

 to justify a conclusion according to that tendency; or in the last 

 analysis, by emphasizing one or two of the reasons on one side, or 

 minimizing one or two on the other, he can arrive at the desired result 

 without conscious strain upon his conscience. 



In the 3rd, 4th and 6th conclusions of Case 12 it is possible to 

 estimate conservatively the degree of probability according to the 

 superior measure or ratio. In the 3rd conclusion the probability that 

 the jury will not agree on a verdict where the evidence on either side 

 is practically equal, depends not on a clear recognition of that equality. 

 If the equality were clearly recognized, the duty of the jury would be 

 to decide for the defendant because the burden of proof rests primarily 

 on the plaintiff, and, the evidence of the defendant in rebuttal being 

 equally strong, the plaintiff would have failed to establish his case. 

 But where there is such a practical equality, every hearer and especially 

 every juror, feeling the challenge to reach a decision, has a tendency to 

 seize arbitrarily upon some one or more of the points, none of them con- 

 clusive, and to lean accordingly to one side or the other. Thus, in 

 the case in question, even the judge, for one or more reasons, among 

 them the erased date on the paper, had a decided leaning toward the 

 defendant. The auditors in the court room and others who were 

 acquainted with the details of the case, also had such leanings, but 

 toward different sides and on different grounds. Largely for this 

 reason, where there is an equality of evidence, there is a tendency for 

 each juror to reach a decision, and the probabilities that he will decide 

 either way are about equal, so that, if p is the probability that a juror 

 will decide for the plaintiff and if q is the contrary probability that he 

 will decide for the defendant, then p = q= 1/2; and where there is 

 this equal probability that each juror will decide either way, the 

 probability that the necessary 10 out of the 12 jurors will decide the 

 same way, and so carry a verdict, would be equal to the term con- 

 taining p^° in the development of (p + qY^. This term is 66^^V 

 = 66 X (1/2)1° X (1/2)2 = 1/62-06, i.e., approximately 1/62 or 1:61 

 The contrary probability that the jury will not agree on a verdict is 

 61/62 or 61:1. This calculation, however, is on the basis that each 

 juror arrives at his decision separately and without a joint effort to 

 agree on a verdict, whereas in fact the jurors meet in common and a 

 strong effort is made to reach an agreement. For this reason the 



