CHAP. V.] OPENING MANHOOD 1847 TO 1850. 113 



Ees possent ; namque officium quod corporis extat 

 Officers atque obstare, id in omni tempore adesset 

 Omnibus. Haud igitur quicquam procedere posset, 

 Principium quoniam cedendi nulla daret res, 

 At nunc per maria ac terras sublimaque cseli 

 Multa modis multis varia ratione moveri 

 Cernimus ante oculos, quse, si non esset Inane, 

 Non tarn sollicito motu privata carerent 

 Quam genita omnino nulla ratione fuissent, 

 Undique materies quoniam stipata quiesset. 1 



Ill connection with his logical studies it should be 

 mentioned that Professor Boole's attempt, made about 

 this time, towards giving to logical forms a mathemati- 

 cal expression, 2 had naturally strong attractions for 

 Clerk Maxwell. 



1 Lucr. de Rer Nat., L 329-345. The following Hamiltonian 

 notions will be found appearing from time to time in Maxwell's corre- 

 spondence and occasional writings : 



1. Opposition of Natural Eealism to " Cosmothetic Idealism " : 



2. Unconscious Mental Modifications : 



3. Distinction between Knowledge and Belief in relation to the 

 doctrine of Perception : 



4. The Infinite or Unconditioned. 



The following passage is worth quoting here, although the experi- 

 ment in question was probably well known to Maxwell before he went 

 to college : 



"... The experiment which Sir W. Hamilton quotes from Mr. 

 Mill, and which had been noticed before either of them by Hartley. 



" It is known that the seven prismatic colours, combined in certain 

 proportions, produce the white light of the solar ray. Now, if the 

 seven colours are painted on spaces bearing the same proportion to one 

 another as in the solar spectrum, and the coloured surface so produced 

 is passed rapidly before the eyes, as by the turning of a wheel, the 

 whole is seen as white." Mill On Hamilton (1st edition, 186 5), p. 286. 



2 Mr. George Boole's first logical treatise, " The Mathematical 

 Analysis of Logic, being an Essay towards a Calculus of Deductive 

 Reasoning," was published in 1847 at Cambridge, by Macmillan, 

 Barclay, and Macmillan. 



I 



