112 INDUCTION. 



laid down in the preceding chapters. When a fact 

 has been observed a certain number of times to be 

 true, and is not in any instance known to be false; if 

 we at once affirm that fact as an universal truth or 

 law of nature, without testing it by any of the four 

 methods of induction, nor deducing it by reasoning 

 from other known laws, we shall in general err 

 grossly: but we are perfectly justified in affirming it 

 as an empirical law, true within certain limits of time, 

 place, and circumstance, provided the number of 

 coincidences is greater than can with any probability 

 be ascribed to chance. The reason for not extending 

 it beyond those limits is, that the fact of its holding 

 true within them may be a consequence of collocations, 

 which cannot be concluded to exist in one place 

 because they exist in another ; or may be dependent 

 upon the accidental absence of counteracting agencies, 

 which any variation of time, or the smallest change of 

 circumstances, may possibly bring into play. If we 

 suppose, then, the subject matter of any generaliza- 

 tion to be so widely diffused that there is no time, no 

 place, and no combination of circumstances, but must 

 afford an example either of its truth or of its falsity, 

 and if it be never found otherwise than true, its truth 

 cannot depend upon any collocation, unless such as 

 exist at all times and places ; nor can it be frustrated 

 by any counteracting agencies, unless by such as 

 never actually occur. It is, therefore, an empirical 

 law coextensive with all human experience ; at which 

 point the distinction between empirical laws and laws 

 of nature vanishes, and the proposition takes its place 

 in the highest order of truths accessible to science. 

 Such a character strictly belongs to the law of 

 universal causation, and to the ultimate principles of 



