394 THE SCIENCE OF LOGIC 



disease ? And what cured a certain kind of disease once ought 

 to be expected to do so again ? This is undoubtedly the line of 

 reasoning followed though so rapidly that in this, as in many 

 similar cases, the intermediate links are scarcely conscious, and 

 leave the impression of only a single step from the one particular 

 case to the other. It is not from the particular instance of the 

 disease that the matron argues, but from the general principle, thus : 



The kind of disease from which Lucy suffered can be cured by 

 certain remedies those administered in her case ; 



But this is an instance of that kind of disease ; 



Therefore it will be cured by those same remedies. 



Again, in arguing from circumstantial evidence, we may be said to be 

 &quot; inferring from particulars,&quot; though we are aided throughout by universal*. 

 &quot; When a jury,&quot; writes Father Joyce, 1 &quot; after weighing a mass of evidence, ac 

 quit or condemn a man accused of burglary, they undoubtedly infer : but they 

 do not employ syllogistic reasoning. They form a critical estimate of what 

 certain particular facts involve. They decide that these facts are compatible 

 or incompatible, as the case may be, with the man s innocence. The evidence 

 taken as a whole may be sufficient to produce certitude : but no sane man 

 would endeavour to state it in the form of a general law. Cardinal Newman 

 has discussed this form of inference at length in his Grammar of Assent. 

 But the difference between the two forms of reasoning was familiar to St. 

 Thomas and was carefully noted by him more than once.&quot; 2 



There is, of course, a process by which mental states are associated so 

 as to suggest one another. But this, whether in man or in animals, is not 

 a logical process a passage from what is apprehended by reason as a rational 

 ground to what is apprehended as a consequent of that ground. Whatever 

 may have been St. Thomas s view about the manner in which we intellectually 

 apprehend particular facts, and reason about concrete matters and his doc 

 trine on the vis cogitativa is not very clear, it is fairly certain, at all events, 

 that if we do reason consciously and logically about such facts, and pass 

 logically from one to another by rational inference, we do so by the aid of 

 universal intellectual truths which reveal a rational connexion between those 

 facts. The difference referred to by St. Thomas between those inferences 

 and inferences from abstract, universal truths, does not consist in the entire ab 

 sence from the former of the universal element present and prominent in the 

 latter, but rather in the fact that the sentient activity is conjoined with the in 

 tellectual activity of the mind in the former inferences in the formation of 

 &quot;singular&quot; concepts and not in the latter. 



Circumstantial evidence is the cumulation or addition of a number of 

 distinct inferences, each pointing with more or less probability towards some 

 concrete, individual conclusion, e.g. &quot; A.B. committed the murder in question &quot;. 



1 Logic, p. 200. 



2&amp;lt;l St. Thomas holds that as these inferences are solely concerned with particu 

 lar facts, they are effected by the vis cogitativa in which sense and intellect meet. 

 See Summa Theol., II., ii., Q. 2, Art. i ; De Pot., Q. 14, Art. i.&quot; ibid., n. 



