158 DOGMATISM AND EVOLUTION 



would hold that the operation of the law is unquestionable 

 that it is merely concealed and not held in abeyance. And, 

 finally, the principle of the lever we find actually operative in 

 the iron crowbar, which, resting on one log, moves another. 

 And let it be considered that apart from such concrete instances 

 as these, the laws in question have no meaning for us. It was 

 not from the consideration of infinite distances, or of the universe 

 as a whole, or of the ultimate constituents of matter, that these 

 laws were derived so much is obvious. And their actual utility 

 in the interpretation of our every-day life, as well as of our 

 scientific experience, is enormous. To suppose that their true 

 application is something utterly different from any application 

 we ever actually make of them is trifling with common sense. 



No, these laws, like other laws, are instruments by means of 

 which we analyze phenomena. They are demonstrated, not from 

 'pure' instances, but from instances in which disturbing factors 

 are as far as possible eliminated; and, both in the more simple 

 and in the more complex instances, their significance is that of 

 the description of a contributing factor in a total process. It is, 

 indeed, to this fact that the exactness of the laws is due, for this 

 is but complementary to the confessed insufficiency of the analy- 

 sis. All inexactness is attributed to further, as yet undistin- 

 guished, conditions. But to say that the laws are approximately 

 verified under approximately perfect conditions is to understate 

 their experimental basis. They are verified with less and less 

 average inexactness as the conditions approach perfection. M. 

 Poincare's theory takes no account of this all-important fact. 

 And it must be added, that even though no single decisive test 

 can ever overthrow these laws, yet, if with increasingly delicate 

 observations the average error should ever fail to decrease, they 

 would be regarded as disproved in their present form, and would 

 have to be materially corrected. 



On the whole, we find no sufficient reason for placing the 

 principles of mechanics in an absolutely different category from 

 those of economics. The essential difference appears to consist 



