18 MODERN SCIENCE: 



bodies in which it was supposed to inhere and make this the cause of 

 their visibility ! Obviously now a common and universal medium is 

 required for this common and universal assumed vibration (just as Newton 

 required a medium for his universal " falling") and so, hey presto ! we 

 have the Undulatory Ether. And having got it we find that to fulfil our 

 requirements it must have a pressure of 17 million million pounds on the 

 square inch, and yet be so rare and tenuous as not to hinder the lightest 

 breath of air ; that while it is thus rare enough to surpass all our powers 

 of direct scrutiny, its vibrations must yet be capable of agitating and 

 breaking up the solidest bodies ; that it must pass freely through some 

 dense and close structures like glass, and yet be excluded by some light 

 and porous, like cork, and so on and on ! In fact we find that it is 

 unthinkable. Against this adamantine, impalpable Ether, as against this 

 instantaneous, untranslatable gravitation, Science bangs its devoted head 

 in vain. Having created these absurdities by the method of " personifi- 

 cation of abstractions " ] or the " reification of concepts/' 2 it seriously and 

 in all good faith tries to understand them ; having dressed up its own 

 Mumbo Jumbo (which it once jeered at religion for doing) it piously 

 ,shuts its eyes and endeavors to believe in it. 



The Atomic Theory 3 affords a good example of the "method of 

 ignorance," when we try to think about material objects generally to 

 generalise about them that is, to find some attribute or attributes common 

 to them, we are at first puzzled. They present such an immense variety. 

 But after a time, by dint of stripping off or abstracting all such attributes 

 or qualities as we think we perceive in one body and not in another as 

 for example, redness, blueness, warmth, saltness, life, intelligence, or 

 what not we find an attribute left, namely resistance to touch, which is 

 common to all material bodies. This quality in the body we call ' ' mass, " 

 and since it is only known by motion, mass and motion become correla- 

 tive attributes which we find useful to class bodies by, not because they 

 represent the various bodies particularly well, 'but because they are found 

 in all bodies ; just as you might class people by their boots not because 

 boots are a very valuable method of classification, but simply because 

 every one wears boots of one kind or another. So far there is no great 

 harm done. But now having by the method of ignorance thought away 

 alUhe qualities of bodies, except the two correlatives of mass and motion, 

 we set about to explain the phenomena of Nature generally by these two 

 "thinks" that are left. We credit these "thinks" (mass and motion) 

 With an independent existence and proceed to derive the rest of phenom- 

 ena from them. The proceeding of course is absurd, and ends by expos- 

 ing its own absurdity. Thinking of mass and motion as existing in the 

 various bodies apart from color, smell, and so forth which of course is 

 not the case we combine the two attributes into one concept, the atom, 



i J. S. Mill. * Stallo. 



s See Stallo's excellent Concepts of Modern Physics. 



