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E. WALTER MAUNDER, E.R.A.S., ON 



expect, that the answer should be expressed in the terms of 

 natural science. They have so ill-defined a conception of the 

 charactel" and scope of science that they suppose that the 

 answer falls within its powers. 



J3ut science has its limitations as well as its powers. As an 

 example of one of the sciences, and as type of all the rest, let 

 us look at ■ astronomy : the oldest, the widest, and the most 

 advanced of all the physical sciences. 



It began with tlie observation made by men that tliere were 

 two great lights in the heavens above us ; the greater that gave 

 light by day, the lesser that gave light by night, and there were 

 the stars also. Then men noted that these two great liglits, by 

 their movements, furnished divisions and measures of time, 

 ^^ext came the observation that there was a correlation between 

 the changes of vegetation on the earth, and certain apparent 

 changes in the heavens ; in the path of the sun across the sky 

 by day, and in the groups of stars visible by night. Later on, 

 some of the stars were perceived to move freely amongst tlie 

 rest, and, after long-continued watching, those movements, 

 which at first had seemed irregular and lawless, were so com- 

 pletely reduced to system that the ])Ositions of these wandering- 

 stars could be predicted for times far in the future, and now 

 the prediction of the movements of the heavenly bodies has 

 become the pre-eminent example of man's achievements in 

 exact science. Step by step men have proceeded from the first 

 mere recognition that there were lights above us, to the know- 

 ledge of their distances, dimensions, weights, chemical constitu- 

 tion, and changes of surface and condition. Nay more ; the 

 scrutiny of bodies removed from us by distances which it is not 

 possible for us to realize, has taught us the existence of 

 chemical elements before we liave recognized therrr upon the 

 earth, and has even instructed us concerning their molecular 

 constitution. 



But astronomy has its limitatioirs : inevitable limitations that 

 apply not to it only, but to all the sciences. It deals only 

 with relations : its observations, its deductions, are only 

 relative. The movements of the sun were noted, first, because 

 they were movements relative to the earth ; the movements of 

 the planets were relative to the stars, and so on ; of aljsolute 

 motion we know nothing. 



Now in every case, we ourselves, we men, furnish the primal 

 relation. Astronomy — and every science — is in its origin, 

 practice and expression, essentially antliroponiorphic ; not 

 because the heavenly Ijodies are themselves human, but because 



