xl 



VI 



Appendix. 



# 



On Probability.— {Part I.) By the Rev. E. Kidd, LL.D. 



[.ffeatf be/ore the Auckland Institute, 1st June, 1874.] 



1. There are two portions of the science of Probability which it is the aim 

 of the following observations in some degree to elucidate. Our present 

 inquiry will be as to the exact nature and relations of what we term Proba- 

 bility, a subject which is, I think, partially involved in confusion. On a 

 subsequent occasion we may consider a certain application of the calculus, 

 which appears to me to merit some development, and which has been hitherto 



unnoticed 



(Popular signification of Probability.) 



mm 



probability to a proposition only when we regard it as not certainly true, but 

 more likely to be true than to be false. The term " probability," as thus used, 

 is equivalent to likelihood or verisimilitude. We find, accordingly, that this is 

 not the primary signification in that language, the Latin, from which the word 

 is deri ved ; and it will not be irrelevant to advert for a moment to its 

 earliest import. Indeed the primary meaning of the word will be found to 

 illustrate very appositely our determination of its present significance. The 

 root prob denoted approbation ; to be probable, probabilis, was to be worthy of 

 being approved. In the classical Latin writers the word has both of these 

 significations, viz., approvable and likely ; while the primary meaning alone 

 pertains to the cognate words probus, probitas, as to our English probity, 

 approbation. We may perceive how the secondary sense flowed from the 

 primary, when we consider that occasions of deliberation respecting the choice 



in 



the only occasions of attempting to prove a proposition ; and that the most 

 approvable course is that from which a good result is the most probable. 

 Demonstrations or proofs were not demanded, in primitive times, for history, 

 theology, jurisprudence, or any science ; but in all eras of human affairs the 

 meed of approbation is awarded to " sage counsel in cumber." 



3. (Scientific Signification. )— -In technical phraseology yet another appli- 

 cation of the term Probability has become established. In this wider 



pertainin 



down 



falsity. The grades of philo- 



generic. 



designati 

 r and the 



contrary 



