250 THE SCIENCE OF LOGIC 



imminent or threatening evil ; and, I think, it will be conceded by 

 all that no risk is run, no chances are taken, if in reliance on the 

 physical laws and moral instincts, I rest assured, for instance, that 

 the solid oaken boards of my room, on which I am standing, will 

 not be suddenly turned into thin air, but will continue to support 

 me ; or that a gay young student, who whilst boating with some 

 of his friends has fallen overboard, will not refuse to grasp the oar 

 held out to him.&quot; l 



260. BELIEF ON AUTHORITY. The moral certitude which we 

 possess about truths of fact on the testimony of our fellow-men, 2 

 is based upon two of the &quot; moral laws &quot; referred to in the previous 

 section, namely, (i) that men can attain to a certain knowledge of 

 the facts of their experience, and (2) that men are naturally truth 

 ful in communicating such information to their fellow-men. In 

 order to give a certain assent to any statement or proposition on the 

 motive of authority, we must be sure that this authority is endowed 

 with two qualifications : (i) knowledge (&quot; sdentia &quot;), and (2) truth 

 fulness (&quot; veracitas&quot;*) : that our authority is not deceived, and is not 

 deceiving us. Manifestly, there is often very large room for the 

 exercise of prudence, discretion, and judicious discrimination, in 

 convincing ourselves of the presence of these two necessary con 

 ditions. And hence the practical impossibility of drawing any 

 sharp line of demarcation between the evidence that will produce 

 the firm assent of strict moral certitude, and the evidence which will 

 guarantee only that very high* degree of probability which is com 

 monly described as &quot; practical &quot; certitude, or &quot; moral&quot; certitude in 

 the wider sense of this expression (233, 249). 



The knowledge which is based upon human testimony as to 

 matters of fact is often described as &quot; belief,&quot; in contradistinction 

 to &quot; science &quot;. There are undoubtedly grounds for the distinction. 

 The motive for the assent which is called &quot; belief&quot; is extrinsic 

 evidence : the testimony of a witness is somethiug extrinsic to the 

 truth to which he testifies ; whereas the motive for &quot; scientific &quot; 

 assent is intrinsic evidence : it is something that is understood or 

 seen in the truth or fact itself. Again, science is universally 

 understood to be a knowledge primarily of general truths or laws, 

 and of facts only as embodying and exemplifying these ; whereas 



1 ROTHER, op. cit., pp. 48, 49 ; cf. ibid., pp. 52-54. 



&quot;Assent to truth on Divine Authority is called Supernatural Faith. Before 

 assenting to a truth revealed by God we must be certain (a) that God exists, and (b) 

 that He has revealed the truth in question. These previous assents are called 

 pn-ambula fidei, preliminaries of faith. 



