CLASSIFICATION AND THE PREDICABLES. 



85 



Accidens, on the other hand, form 

 no part of the essence, but are predi- 

 cated of the species only accidentally. 

 Both are Accidents, in the wider 

 sense in which the accidents of a 

 thing are opposed to its essence ; 

 though in the doctrine of the Pre- 

 dicables, Accidens is used for one sort 

 of accident only, Proprium being 

 another sort. Proprium, continue the 

 schoolmen, is predicated accidentaUy 

 indeed, but necessarily ; or, as they 

 further explain it, signifies an attribute 

 which is not indeed part of the essence, 

 but which flows from, or is a con- 

 sequence of, the essence, and is, 

 therefore, inseparably attached to the 

 species ; e.g. the various properties of 

 a triangle, which, though no part of 

 its definition, must necessarily be pos- 

 sessed by whatever comes under that 

 definition. Accidens, on the contrary, 

 has no connection whatever with the 

 essence, but may come and go, and the 

 species still remain what it was before. 

 If a species could exist without its 

 Propria, it must be capable of existing 

 without that on which its Propria are 

 necessarily consequent, and therefore 

 without its essence, without that which 

 constitutes it a species. But an Acci- 

 dens, whether separable or inseparable 

 from the species in actual experience, 

 may be supposed separated, without 

 the necessity of supposing any other 

 alteration ; or at least, without sup- 

 posing any of the essential proper- 

 ties of the species to be altered, since 

 with them an Accidens has no connec- 

 tion. 



A Proprium, therefore, of the species, 

 may be defined, any attribute which 

 belongs to all the individuals included 

 in the species, and which, though not 

 connoted by the specific name, (either 

 ordinarily if the classification we are 

 considering be for ordinary purposes, 

 or specially if it be for a special pur- 

 pose, ) yet follows from some attribute 

 which the name either ordinarily or 

 specially connotes. 



One attribute may follow from an- 

 other in two ways ; and there are con- 

 sequently two kinds of Proprium. It 



may follow as a conclusion follows pre- 

 mises, or it may follow as an effect 

 follows a cause. Thus, the attribute 

 of having the opposite sides equal, 

 which is not one of those connoted 

 by the word Parallelogram, neverthe- 

 less follows from those connoted by it, 

 namely, from having the opposite sides 

 straight lines and parallel, and the 

 number of sides four. The attribute, 

 therefore, of having the opposite sides 

 equal, is a Proprium of the class par- 

 allelogram ; and a Proprium of the 

 first kind, which follows from the con- 

 noted attributes by way of demonstra- 

 tion. The attribute of being capable 

 of understanding language is a Pro- 

 prium of the species man, since, with- 

 out being connoted by the word, it 

 follows from an attribute which the 

 word does connote, viz. from the attri- 

 bute of rationality. But this is a 

 Proprium of the second kind, which 

 follows by way of causation. How it 

 is that one property of a thing follows, 

 or can be inferred, from another ; 

 under what conditions this is possi- 

 ble, and what is the exact meaning of 

 the phrase ; are among the questions 

 which will occupy us in the two suc- 

 ceeding Books. At present it needs 

 only be said, that whether a Proprium 

 follows by demonstration or by causa- 

 tion, it follows necessarily ; that is to 

 say, its not following would be incon- 

 sistent with some law which we re- 

 gard as a part of the constitution either 

 of our thinking faculty or of the uni- 



§ 8. Under the remaining predic- 

 able, Accidens, are included all attri- 

 butes of a thing which are neither in- 

 volved in the signification of the name, 

 (whether ordinarily or as a term of 

 art,) nor have, so far as we know, any 

 necessary connection with attributes 

 which are so involved. They are 

 commonly divided into Separable and 

 Inseparable Accidents. Inseparable 

 accidents are those which — although 

 we know of no connection between 

 them and the attributes constitutive of 

 the species, and although, therefore, 



