Civilisation : Its Cause and Cure 



well be more distinct from each other than these ; 

 yet if an eclipse had to be calculated for next year 

 it would scarcely matter which theory was used. 

 The truth is that the actual problem is so vast that 

 a prediction of a few years in advance only touches 

 the fringe of it so to speak; yet if the fulfilment of 

 the prediction were taken as a proof of the theory 

 in each of these different cases, it would lead in 

 the end to the most hopelessly contradictory 

 results. 



The success of a prediction therefore only 

 shows that the theory on which it is founded has 

 had practical value so far as a working hypothesis. 

 As working hypotheses, and as long as they are 

 kept down to brief steps which can be verified^ 

 the scientific theories are very valuable — indeed 

 we could not do without them ; but when they 

 are treated as objective facts — when, for instance, 

 the '' law of gravitation " — derived as it is from a 

 brief study of the heavenly bodies — has a universal 

 truth ascribed to it, and is made to apply to pheno- 

 mena extending over millions of years, and to 

 warrant unverifiable prophecies about the plane- 

 tary orbits, or statements about the age of the earth 

 and the duration of the solar system — all one 

 can say is that those who argue so are flying off 

 at a tangent from actual facts. For as the tangent 

 represents the direction of a curve over a small 

 arc, so these theories represent the bearing of 

 facts well enough over a small region of observa- 

 tion ; but as following the tangent we soon lose 

 the curve, so following these theories for any dis- 



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