PREFACE. , T 



illustration, and to condemn the principle to which it 

 applies as unsound, because they happen to know 

 facts which are at variance with the particular ex- 

 ample brought forward. In this way, there is per- 

 haps no one rule which I have advanced to which 

 some individual case may not be plausibly opposed. 

 But it does not necessarily follow that the principle 

 or rule is thereby disproved. An example may be 

 badly chosen, and yet the truth it is meant to con- 

 vey may be as much a truth as before. Instead, 

 therefore, of at once condemning a proposition on 

 account of a single apparent exception, it will be 

 better to extend the inquiry, and discover whether 

 any peculiarity of situation or constitution has inter- 

 fered to modify the result, and to condemn only 

 when evidence of inaccuracy is obtained. Thus, 

 because some drunkards have enjoyed good health, 

 and lived to an unusually old age, we are by no 

 means entitled to infer that drinking was the cause 

 of the good health, and that if we would all drink as 

 freely, we should all live as long. An example of 

 this kind, far from disproving the principle that ar- 

 dent spirits are prejudicial to the human frame, only 

 establishes the fact that individuals exist who, from 

 some idiosyncrasy, are better able than others to re- 

 sist their bad effects ; and, in like manner, when I 

 state, as a general proposition, that severe muscular 

 exertion is hurtful during rapid growth, I do not 

 consider it as any argument against the fact to say, 

 that A. B. underwent great exertion when growing 

 without being injured by it. The general principle 

 obviously remains unaffected by any such instances. 

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