THE DISCOVERY OF LAWS 69 



the new laws propounded must still be such that they 

 order the old experience, and they must therefore present 

 some features of great similarity to the old laws. Which 

 of the two alternatives we shall adopt depends upon 

 which method leads to the most satisfactory ordering of 

 the complete experience. For this reason the first 

 alternative is never adopted if the second is available ; 

 for it means that we must leave unordered a portion of 

 experience which we thought could be ordered. 



This is, I believe, the attitude that is actually adopted 

 by men of science in establishing laws. And if that is 

 so, the conception of prediction does not enter into explicit 

 consideration at all. Wejiojiot try to findjaws tha 

 will predict ; J^_gjtiyjy to find laws thatjvyill jpj^j 

 experience thatjvve have. It is possible to adopt that 

 attitude because, although we know that we shall have 

 future experience which has not been taken into considera- 

 tion, that future experience can never force us to abandon 

 the ground we have gained and to " disorder " the order 

 that has been established. Whatever the experience 

 may be, it will be possible either to order the increased 

 volume of experience, or else to reject altogether from the 

 subject-matter of science some portion of it, leaving only 

 the remainder to be ordered. 



THE VALUE OF LAWS 



But to the practical man that attitude will not seem 

 very satisfactory. It appears to deprive science of all 

 objective value. If scientific laws are true, only becaus'e 

 they can always be re-interpreted so that nothing can 

 prove them false, then science is merely a childish game 

 unworthy of the attention of any serious man. If, when 

 science asserts that the sun will rise to-morrow, it only 

 means that, if the sun does not rise, we propose to alter 

 somewhat our laws of the solar system, science is mere 

 trifling. What the plain man means by that assertion 



