52 PROGRESS OF SCIENCE IN THE CENTURY, 



energy always persist however their forms of expres- 

 sion may change, here are two other uniformities 

 or, perhaps, the two are one ; but there are not many 

 other conclusions which admit of the same univer- 

 sality of application and verifiability of accuracy. 

 We know the " law of biogenesis," omne vivum e 

 vivo, to mean that, so far as our experience goes, every 

 living creature springs from some other living crea- 

 ture; we do not know of any exception to the state- 

 ment, but we see no warrant in this for asserting that 

 the so-called law was, or will be, or even is always 

 true. And the same doubt, which becomes more as- 

 sertive when we consider this last instance, is not 

 silent even in regard to the alleged indestructibility 

 of matter or the alleged indestructibility of power. 

 It does not seem particularly forcible to retort that 

 " one cannot conceive of the reverse happening," for 

 it is not so long since a belief in spontaneous genera- 

 tion was widespread, or since the idea that the earth 

 was not the hub of the universe was deemed by many 

 and these not small-brained men " quite incon- 

 ceivable." And these were the very words of Mother 

 Grundy when she first heard of the Doctrine of De- 

 scent 



In short, is there not a radical fallacy in the phrnse 

 " The Uniformity of Nature," since our so-called 

 natural laws are only descriptive formulae of what 

 is seen and known in given conditions of space and 

 time, neither "governing nature," nor "explaining 

 nature " ? As descriptive formulae of observed phe- 

 nomena, presumably descriptive of similar unobserved 

 phenomena, they make it easier for us to look out 

 upon the world without intellectual biliousness in- 

 deed with the greatest of joy, to follow the course of 

 events with some appreciation of their orderliness, 



