LAW OF CAUSATION. 241 



\ The cause, then, philosophically speaking, is the sum total of the condi- 

 tions, positive and negative taken together ; the whole of the contingencies 

 of every description, which being realized, the consequent invariably fol- 

 lows.'^The negative conditions, however, of any phenomenon, a special 

 enun*CT'ation of which would generally be very prolix, may be all summed 

 up under one head, namely, the absence of preventing or counteracting 

 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 retards the 

 upward motion of a projectile, and deflects it into a parabolic trajectory, 

 it produces, in so doing, the very same kind of effect, and even (as mathe- 

 maticians know) the same quantity of effect, as it does in its ordinary op- 

 eration of causing the fall of bodies when simply deprived of their support. 

 If an alkaline solution mixed with an acid destroys its sourness, and pre- 

 vents it from reddening vegetable blues, it is because the specific effect of 

 the alkali is to combine with the acid, and form a compound 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 according to which they produce their own,* enables us, by 

 establishing the general axiom that all causes are liable to be counteracted 

 in their effects by one another, to dispense with the consideration of nega- 

 tive conditions entirely, and limit the notion of cause to the assemblage of 

 the positive conditions of the phenomenon : one negative condition invaria- 

 bly understood, and the same in all instances (namely, the absence of coun- 

 teracting causes) being sufiicient, along with the sum of the positive condi- 

 tions, to make up the whole set of circumstances on which the phenomenon 

 is dependent. 



§ 4. Among the positive conditions, as we have seen that there are some 



mere negative conditions ; but they happened to be the only ones which there could be any 

 necessity to state ; for he walked, most likely, in exactly his usual manner, and the nega- 

 tive conditions made all the difference. Again, if a person were asked why the army of 

 Xerxes defeated that of Leonidas, he would probably say, because they were a thousand times 

 the number ; but I do not think he 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 Powell, the opening of flood-gates is said to be the cause of the flow of water ; yet the 

 ictive force is exerted by the water itself, and opening the flood-gates merely supplies a nega- 

 tive condition. The reviewer adds, "There are some conditions absolutely passive, and yet 

 ibsohitely necessary to physical phenomena, viz., the relations of space and time; and to 

 ;hese no one ever applies the word cause without being immediately arrested by those who 

 lear him." Even from this statement I am compelled to dissent. Few persons would feel it 

 ncongruous to say (for example) that a secret became known because it was spoken of when 

 \. B. was within hearing ; which is a condition of space : or that the cause why one of two 

 )articular trees is taller than the other, is that it has been longer planted ; which is a condi- 

 ion of time. 



* There are a few exceptions ; for there are some properties of objects which seem to be 

 )urely preventive ; as the property of opaque bodies, by which they intercept the passage of 

 ight. This, as far as we are able to understand it, appears an instance not of one cause 

 ounteracting another by the same law whereby it produces its own effects, but of an agency 

 vhich manifests itself in no other way than in defeating the effects of another agency. If 

 ve knew on what other relations to light, or on what peculiarities of structure, opacity de- 

 ends, we might find that this is only an apparent, not a i-eal, exception to the general propo- 

 ition in the text. In any case it needs not affect the practical application. The formula 

 rhich includes all the negative conditions of an effect in the single one of the absence of 

 ounteracting causes, is not violated by such cases as this ; though, if all counteracting agen- 

 ies were of this description, there would be no purpose served by employing the formula. 



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