48 INDUCTION. 



simpler laws from which they result; not in the same degree 

 to he relied on as universally true. The inferiority of evidence, 

 however, which attaches to this class of laws, is trifling, com- 

 pared with that which is inherent in uniformities not known 

 to he laws of causation at all. So long as these are unresolved, 

 we cannot tell on how many collocations, as well as laws, their 

 truth may he dependent; we can never, therefore, extend 

 them with any confidence to cases in which we have not 

 assured ourselves, hy trial, that the necessary collocation of 

 causes, whatever it may he, exists. It is to this class of laws 

 alone that the property, which philosophers usually consider 

 as characteristic of empirical laws, helongs in all its strictness ; 

 the property of being unfit to be relied on beyond the limits 

 of time, place, and circumstance, in which the observations 

 have been made. These are empirical laws in a more em- 

 phatic sense ; and when I employ that term (except where the 

 context manifestly indicates the reverse) I shall generally mean 

 to designate those uniformities only, whether of succession 

 or of coexistence, which are not known to be laws of 

 causation. 



