THE EXPLANATION OF LAWS 91 



or theories and not laws as the product of the internal 

 world of the intellect. F"For both theories and laws derive 

 their ultimate value from their concordance with nature 

 and both arise from mental processes of the same kin3^ 

 Moreover, as has been suggested already, in the more 

 highly developed sciences of to-day theories play a very 

 large part in determining laws ; they not only suggest 

 laws which are subsequently confirmed by experimental 

 investigation, but they also decide whether suggested 

 laws are or are not to be accepted. For, as our discussion 

 in the previous chapter showed, experiment alone cannot 

 decide with perfect definiteness whether or no a law is 

 to be accepted ; there are always loopholes left which 

 enable us to reject a law, however much experimental 

 evidence may suggest it and enable us to maintain a law 

 (slightly modified) even when experimental evidence seems 

 directly to contradict it. An examination of any actual 

 science will show that the acceptance of a law is very 

 largely determined by the possibility of explaining it 

 by means of a theory ; if it can be so explained, we are 

 much more ready to accept it and much more anxious 

 to maintain it than we should be if it were not the conse- 

 quence of some theory. Indeed many laws in science are 

 termed " empirical " and regarded with a certain amount 

 of suspicion ; if we inquire we find that an empirical law 

 is simply one of which no theoretical explanation is known. 

 In the science of physics at least, it would almost be more 

 accurate to say that we believe our laws because they are 

 consequences of our theories than to say that we believe 

 our theories because they predict and explain true laws ! 

 On such grounds I reject the view (though it is generally 

 prevalent) .that laws are any less the product of imagina- 

 tive thought than ?rp fhrnrip.^ The, problem why nature 

 conforms with our intellectual desires arises just as clearly 

 with one as with the other. Nevertheless it is doubtless 

 true that the 'personal and imaginative element is more 



