40 Presidential Address 



To show that I am not exaggerating 

 the modern tendency towards discon- 

 tinuity, I quote, from M. Poincare's 

 Dernieres Pensees, a proposition which 

 he announces in italics as representing a 

 form of Professor Planck's view of which 

 he apparently approves: 



A physical system is susceptible of a finite 

 number only of distinct conditions; it jumps 

 from one of these conditions to another without 

 passing through a continuous series of inter- 

 mediate conditions. 



Also this from Sir Joseph Larmor's 

 Preface to Poincare's Science and 

 Hypothesis: 



Still more recently it has been found that 

 the good Bishop Berkeley's logical jibes against 

 the Newtonian ideas of fluxions and limiting 

 ratios cannot be adequately appeased in the 

 rigorous mathematical conscience, until our 

 apparent continuities are resolved mentally 

 into discrete aggregates which we only partially 

 apprehend. The irresistible impulse to atomise 

 everything thus proves to be not merely a dis- 

 ease of the physicist: a deeper origin, in the 

 nature of knowledge itself, is suggested. 



