2lS 



INDUCTION. 



acting causes. The convenience of 

 this mode of expression is mainly 

 grounded on the fact, that the effects 

 of any cause in counteracting another 

 cause may in most cases be, with 

 strict scientific exactness, regarded 

 as a mere extension of its own proper 

 and separate effects. If gravity re- 

 tards the upward motion of a projec- 

 tile, and deflects it into a parabolic 

 trajectory, it produces, in so doing, 

 the very same kind of effect, and 

 even (as mathematicians know) the 

 same quantity of effect, as it does in 

 its ordinary operation of causing the 

 fall of bodies when simply deprived 

 of their support If an alkaline solu- 

 tion mixed with an acid destroys its 

 sourness, and prevents it from redden- 

 ing vegetable blues, it is because the 

 specific effect of the alkali is to com- 

 bine with the acid, and form a com- 

 pound with totally different qualities. 

 This property, which causes of all 

 descriptions possess, of preventing the 

 effects of other causes by virtue (for 

 the most part) of the same laws ac- 

 cording to which they produce their 

 own,* enables us, by establishing the 



do not think be would say it was because 

 they fought, though that was the element 

 of active force. To borrow another example, 

 used by Mr. Grove and by Mr. Baden Po- 

 well, the opening of floodgates is said to 

 be the cause of the flow of water ; yet the 

 active force is exerted by the water itself, 

 and opening the floodgates merely supplies 

 a negative condition. The reviewer adds, 

 " There are some conditions absolutely pas- 

 sive, and yet absolutely necessary to phy- 

 sical phenomena, viz. the relations of space 

 and time ; and to these no one ever applies 

 the word cause without being immediately 

 arrested by those who hear him." Even 

 from this statement I am compelled to 

 dissent. Few persons would feel it incon- 

 gruous to say (for example) that a secret 

 became known because it was spoken of 

 when A. B. was within hearing ; which is 

 a condition of space; or that the cause 

 why one of two particular trees is taller 

 than the other is that it has been longer 

 planted ; which is a condition of time. 



* There are a few exceptions ; for there 

 are some properties of objects which seem 

 to be purely preventive ; as the property 

 of opaque bodies by which they intercept 

 the passage of light. This, as far as we 

 are able to understand it, appears an in- 

 stance not of one cause counteracting an- 



general axiom that all causes ai*G 

 liable to be counteracted in their 

 effects by one another, to dispense 

 with the consideration of negative 

 conditions entirely, and limit the 

 notion of cause to the assemblage of 

 the positive conditions of the pheno- 

 menon : one negative condition in- 

 variably understood, and the same in 

 all instances (namely, the absence of 

 counteracting causes) being sufficient, 

 along with the sum of the positive 

 conditions, to make up the whole set 

 of circumstances on which the pheno- 

 menon is dependent. 



§ 4. Among the positive conditions, 

 as we have seen that there are some 

 to which, in common parlance, the 

 term cause is more readily and fre- 

 quently awarded, so there are others 

 to which it is, in ordinary circum- 

 stances, refused. In most cases of 

 causation a distinction is commonly 

 drawn between something which acts, 

 and some other thing which is acted 

 upon ; between an agent and a. patient. 

 Both of these, it would be universally 

 allowed, are conditions of the pheno- 

 menon ; but it would be thought 

 absurd to call the latter the cause, 

 that title being reserved for the 

 former. The distinction, however, 

 vanishes on examination, or rather 

 is found to be only verbal, arising 

 from an incident of mere expression, 

 namely, that the object said to be 

 acted upon, and which is considered 

 as the scene in which the effect takes 



other by the same law whereby it produces 

 its own effects, but of an agency which 

 manifests itself in no other way than in 

 defeating the effects of another agency. If 

 we knew on what other relations to light, 

 or on what peculiarities of structure, 

 opacity depends, we might find that this 

 is only an apparent, not a real exception 

 to the general proposition in the text. In 

 any case it needs not affect the practical 

 application. The formula v^^hich includes 

 all the negative conditions of an effect in 

 the single one of the absence of counter- 

 acting causes, is not violated by such cases 

 as this ; though if all counteracting agen- 

 cies were of this description, there would 

 be no purpose served by employing the for- 

 mula. 



