216 THE SCIENCE OP LOGIC 



secondly, what about facts that fall outside our own individual 

 experience, whether these be past, or present, or future ? Apart 

 from the moral certitude we may have of the occurrence of any 

 such facts on the extrinsic evidence of human testimony or au 

 thority, can we have physical certitude about them ? Obviously, 

 they do not present their own intrinsic evidence to us immedi 

 ately ; but they may do so mediately, i.e. by way of some known 

 and proved connexions between them and certain other facts 

 which we have ourselves experienced directly and immediately. 

 We may be certain, for instance, that, besides the bars of iron 

 we ourselves have seen being elongated by heat, other bars of 

 iron have been, or are being, or will be, likewise elongated by 

 heat, provided that in such cases, past, present, or future, certain 

 conditions be fulfilled. But, note that our certitude here is about 

 the conditional occurrence of these other instances : we are certain 

 that they have occurred, or do, or will occur, not absolutely, but 

 contingently on the fulfilment of certain conditions such for 

 instance as the actual existence of other bars of iron and other 

 sources of heat, the repetition in them of the physical conditions 

 involved in the law that &quot; heat elongates iron bars,&quot; the uni 

 formity of the action of physical causes, the absence of interfering 

 causes (224). Our certitude of their occurrence asyfo/j, involves, 

 and is based upon, our certitude of the universal prevalence and 

 validity of laws within the domain of these facts. Law is the 

 rational connecting link between experienced facts and unex 

 perienced facts. Hence, our certitude about such unexperienced 

 facts is not precisely certitude that they did, or do, or will occur; 

 but, rather, that they must occur. It is a mediate, inferential 

 certitude, based on prior certitude regarding the laws. Now, of 

 the laws on which these inferences are based, some, no doubt, 

 are absolutely and self-evidently necessary, such as the principle 

 of causality ; but others are inductively established laws, the 

 necessity of which we have seen to be, in ultimate analysis, not 

 an. absolute, unconditional necessity, but rather a conditional 

 necessity, contingent on the will of the Supreme Being who rules 

 the whole created universe (224). This kind of certitude, which 

 we thus obtain by induction from experienced facts, regarding 

 the conditional prevalence of laws, and the conditional occurrence 

 of unexperienced facts inferred from the latter, is likewise com 

 monly recognized and described as physical certitude. 



Moral certitude is the certitude of belief based upon authority ; 



