574 



PHILOSOPHICAL THOUGHT. 



at a distance, the latter put into the place of the forces 

 of nature the conception of Energy. In the same 

 degree as these modern ideas have been introduced into 

 the scientific view of nature, the older astronomical and 

 atomic views have been somewhat discredited or thrust 

 into the background.^ 



It then dawned upon some of the leaders of scientific 

 thought that science when it deals with natural pheno- 

 mena is not tied to one rigid system of conceptions, that 

 its aim is not to explain but simply to describe the 

 things and processes around us in the simplest and most 

 convenient manner ; that different methods exist by 

 which this can be done, but that none of these methods 

 or systems give an insight into the nature of things, but 

 only afford to the thinking mind the means of con- 

 necting the processes and phenomena of nature with 

 each other. This logical connection leads from the 



^ As already shown in the first 

 section of this History, however 

 (chapter vii., p. 198), the atomic 

 or corpuscular view has latterly 

 been strengthened by recent re- 

 search in electrical science, which 

 favours a corpuscular theory of 

 electricity, and to this we may add 

 the importance which Mendelian 

 theories attach to definite units 

 of character in living organisms : 

 these are assumed to persist and to 

 be transmitted through heredity, 

 frequently after having been ap- 

 parently lost or become useless 

 " survivals." It seems, indeed, im- 

 possible for an ultimate explanation 

 to conceive of a plenum or con- 

 tinuum in space without assuming 

 at the same time that such a 

 plenum contains discontinuities 

 which admit of portions of this 

 plenum being defined, and preserv- 

 ing their identity : this introduces 



again the atomic view, the concep- 

 tion of discrete particles. The 

 vortex-atom theory of Lord Kelvin, 

 " the discovery of the types of 

 permanent motion, which could 

 combine and interact with each 

 other without losing their indi- 

 viduality," seems so far the only 

 image which we possess of discon- 

 tinuities in a plenum depending 

 entirely on different modes of 

 motion of the same all-pervading 

 substance termed the universal 

 fluid or Ether. It is, however, 

 also interesting to note how the 

 celebrated author of the vortex - 

 atom theory latterly abandoned his 

 own hj'pothesis — ' ' the idea that 

 a mere configuration of motion 

 suffices " — as not likely to be 

 " helpful in respect to crystalline 

 configurations, or electrical, chemi- 

 cal, or gravitational forces." See 

 ante, vol. ii. p. 182, note 2. 



