238 INDUCTION. 



plete, unless in some shape or othei' we intvodnce them all. A man takes 

 mercury, goes out-of-doors, and catches cold. We say, perhaps, that the 

 cause of his taking cold was exposure to the air. It is clear, however, 

 that his having taken mercuiy may have been a necessary condition of 

 his catching cold ; and though it might consist with usage to say that the 

 cause of his attack was exposure to the air, to be accurate we ought to 

 say that the cause was exposure to the air while under the effect of mei'- 

 cury. 



If we do not, when aiming at accuracy, enumerate all the conditions, it 

 is only because some of them will in most cases be understood without 

 being expressed, or because for the purpose in view they may without 

 detriment be overlooked. For example, when we say, the cause of a man's 

 death was that his foot sHpped in climbing a ladder, we omit as a thing 

 unnecessary to be stated the circumstance of his weight, though quite as 

 indispensable a condition of the effect which took place. When we say 

 that the assent of the crown to a bill makes it law, we mean that the as- 

 sent, being never given until all the other conditions are fulfilled, makes up 

 the sum of the conditions, though no one now regards it as the principal 

 one. When the decision of a legislative assembly has been determined 

 by the casting vote of the chairman, we sometimes say that this one person 

 w^as the cause of all the effects which resulted from the enactment. Yet 

 we do not really suppose that his single vote contributed more to the re- 

 sult than that of any other person who voted in the afiirinative ; but, for 

 the purpose we have in view, which is to insist on his individual responsi- 

 bility, the part which any other person had in the transaction is not ma- 

 terial. 



In all these instances the fact which was dignified with the name of 

 cause, was the one condition which came last into existence. But it must 

 not be supposed that in the employment of the term this or any other rule 

 is always adhered to. Nothing can better show the absence of any scien- 

 tific ground for the distinction between the cause of a phenomenon and its 

 conditions, than the capricious manner in which we select from among the 

 conditions that which we choose to denominate the cause. However nu- 

 merous the conditions may be, there is hardly any of them which may not, 

 according to the purpose of our immediate discourse, obtain that nominal 

 pre-eminence. This will be seen by analyzing the conditions of some one 

 familiar phenomenon. For example, a stone thrown into water falls to the 

 bottom. What are the conditions of this event? In the fii'st place there 

 must be a stone, and water, and the stone must bo thrown into the water ; 

 but these suppositions forming part of the enunciation of the phenomenon 

 itself, to include them also among the conditions would be a vicious tautol- 

 ogy ; and this class of conditions, therefore, have never received the name 

 of cause from any but the Aristotelians, by whom they were called the ma- 

 terial cause, causa materialis. The next condition is, there must be an 

 earth : and accordingly it is often said, that the fall of a stone is caused by 

 the earth ; or by a power or property of the eai-th,or a force exerted by the 

 earth, all of which are merely roundabout ways of saying that it is caused 

 by the earth ; or, lastly, the earth's attraction ; which also is only a technical 

 mode of saying that the earth causes the motion, with the additional par- 

 ticularity that the motion is toward the earth, which is not a character of 

 the cause, but of the effect. Let us now pass to another condition. It is 

 not enough that the eai-th should exist; the body must be within that dis- 

 tance from it, in which the earth's attraction preponderates over that of any 



