ERRORS ARISING FROM UNPROVED HYPOTHESES. 121 



but a few days, or even but a few hours, contrasts no less 

 strongly with human longevity. This comparison brings 

 the relative nature of all measurement of time very clearly 

 before us.' l 



The existence of design in an act does not necessarily 

 prove the co-existence of intention or will ; for instance, a 

 crystal builds itself to a particular shape in obedience to 

 the forces latent in its particles and in the surrounding 

 medium, and if either of these are altered the design of 

 the crystal is liable to change ; thus crystals of particular 

 substances, if formed at a low temperature, have one 

 shape, and if at a high temperature, another. An acid, 

 also, under one set of conditions, will select one particular 

 base, and, under other conditions, a different one, and in 

 each case it selects a determinate but a different weight. 



The supremacy of law in nature is proved especially 

 by the almost infinite number of created living things, 

 which, through no fault of their own, do not fulfil the 

 purpose for which they were fitted. ' To work in vain, 

 in the sense of producing means of life which are not 

 used, embryos which are never vivified, germs which are 

 not developed, is so far from being contrary to the usual 

 proceedings of nature, that it is an operation which is 

 constantly going on in every part of nature. Of the 

 vegetable seeds which are produced, what an infinitely 

 small proportion ever grow into plants ! Of animal ova, 

 how exceedingly few become animals in proportion to 

 those that do not, and that are wasted, if this be waste ! 

 It is an odd calculation, which used to be repeated as 

 a wonderful thing, that a single female fish contains in 

 its body 200 millions of ova, and thus might, of itself 

 alone, replenish the seas, if all these were fostered into 



1 Haeckel, History of Creation, vol. ii. p. 338. 



