444 POPULAR SCIENCE MONTHLY 



hazards we have established rules. It is the aggregate of these rules 

 that is called science. 



It is thus that men, desirous of diversion, have instituted rules 

 of play, like those of tric-trac for instance, which, better than science 

 itself, could rely upon the proof by universal consent. It is thus like- 

 wise that, unable to choose, but forced to choose, we toss up a coin, 

 head or tail to win. 



The rule of tric-trac is indeed a rule of action like science, but 

 does any one think the comparison just and not see the difference? 

 The rules of the game are arbitrary conventions, and the contrary 

 convention might have been adopted, ivhich would have been none the 

 Jess good. On the contrary, science is a rule of action which is suc- 

 cessful, generally at least, and I add, while the contrary rule would 

 not have succeeded. 



If I say, to make hydrogen cause an acid to act on zinc, I formu- 

 late a rule which succeeds; I could have said, make distilled water 

 act on gold; that also would have been a rule, only it would not have 

 succeeded. If therefore scientific ' recipes ' have a value, as rule of 

 action, it is because we know they succeed, generally at least. But to 

 know this is to know something and then why tell us we can know 

 nothing ? 



Science foresees, and it is because it foresees, that it can be useful 

 and serve as rule of action. I well know that its previsions are often 

 contradicted by the event; that shows that science is imperfect and if 

 I add that it will always remain so, I am certain that this is a 

 prevision which, at least, will never be contradicted. Always the 

 scientist is less often mistaken than a prophet who should predict at 

 random. Besides the progress though slow is continuous, so that 

 scientists, though more and more bold, are less and less misled. This 

 is little, but it is enough. 



I well know that M. LeEoy has somewhere said that science was 

 mistaken oftener than one thought, that comets sometimes played 

 tricks on astronomers, that scientists, who apparently are men, did 

 not willingly speak of their failures and that, if they should speak of 

 them, they would have to count more defeats than victories. 



That day, M. LeRoy evidently overreached himself. If science did 

 not succeed, it could not serve as rule of action; whence would it get 

 its value ? Because it is ' lived,' that is, because we love it and believe 

 in it? The alchemists had recipes for making gold, they loved them 

 and had faith in them, and yet our recipes are the good ones, although 

 our faith be less lively, because they succeed. 



There is no escape from this dilemma; either science does not 

 enable us to foresee, and then it is valueless as rule of action ; or else 

 it enables us to foresee in a fashion more or less imperfect, and then 

 it is not without value as means of knowledge. 



