CO-EXISTENCES INDEPENDENT OF CAUSATION. 381 



specting the co-existence of properties, 

 a degree of certainty to which, if the 

 properties should happen to be the 

 result of causes, it would have no 

 claim. A generalisation respecting 

 co-existence, or, in other words, re- 

 specting the properties of Kinds, may 

 be an ultimate truth, but it may, also, 

 be merely a derivative one ; and 

 since, if so, it is one of those deriva- 

 tive laws which are neither laws of 

 causation nor have been resolved into 

 the laws of causation on which they 

 depend, it can possess no higher de- 

 gree of evidence than belongs to an 

 empirical law. 



§ 4. This conclusion will be con- 

 firmed by the consideration of one 

 great deficiency, which precludes the 

 application to the ultimate uniformi- 

 ties of co-existence of a system of 

 rigorous scientific induction, such as 

 the uniformities in the succession of 

 phenomena have been found to ad- 

 mit of. The basis of such a system 

 is wanting ; there is no general axiom, 

 standing in the same relation to the 

 uniformities of co-existence as the law 

 of causation does to those of succes- 

 sion. The Methods of Induction ap- 

 plicable to the ascertainment of causes 

 and effects are grounded on the prin- 

 ciple that everything which has a 

 beginning must have some cause or 

 other ; that among the circumstances 

 which actually existed at the time of 

 its commencement, there is certainly 

 some one combination on which the 

 effect in question is unconditionally 

 consequent, and on the repetition of 

 which it would certainly again recur. 

 But in an inquiry whether some Kind 

 (as crow) universally possesses a cer- 

 tain property (as blackness), there is 

 no room for any assumption analogous 

 to this. We have no previous cer- 

 tainty that the property must have 

 something which constantly co-exists 

 with it — must have an invariable co- 

 existent in the same manner as an 

 event must have an invariable ante- 

 cedent. When we feel pain, we must 

 be in some circumstances under which, 



if exactly repeated, we should always 

 feel pain. But when we are conscious 

 of blackness, it does not follow that 

 there is something else present of 

 which blackness is a constant accom- 

 paniment. There is, therefore, no 

 room for elimination ; no Method of 

 Agreement or Difference, or of Con- 

 comitant Variations (which is but a 

 modification either of the Method of 

 Agreement or of the Method of Dif- 

 ference). We cannot conclude that 

 the blackness we see in crows must 

 be an invariable property of crows, 

 merely because there is nothing else 

 present of which it can be an in- 

 variable property. We therefore in- 

 quire into the truth of a proposition 

 like " All crows are black," under the 

 same disadvantage as if, in our in- 

 quiries into causation, we were com- 

 pelled to let in, as one of the possi- 

 bilities, that the effect may in that 

 particular instance have arisen with- 

 out any cause at all. 



To overlook this grand distinction 

 was, as it seems to me, the capital 

 error in Bacon's view of inductive 

 philosophy. The principle of elimi- 

 nation, that great logical instrument 

 which he had the immense merit of 

 first bringing into general use, he 

 deemed applicable in the same sense, 

 and in as unqualified a manner, to 

 the investigation of the co-existences 

 as to that of the successions of pheno- 

 mena. He seems to have thought 

 that as every event has a cause or 

 invariable antecedent, so every pro- 

 perty of an object has an invariable 

 co-existent, which he called its Form ; 

 and the examples he chiefly selected 

 for the application and illustration of 

 his method were inquiries into such 

 Forms — attempts to determine in 

 what else all those objects resembled 

 which agreed in some one general 

 property, as hardness or softness, 

 dryness or moistness, heat or cold- 

 ness. Such inquiries could lead to 

 no result. The objects seldom have 

 any such circumstances in common. 

 They usually agree in the one point 

 inquired into, and in nothing else. 



