PROFESSOR AT HEIDELBERG 267 



even after his Academic Discourse in 1878, on ' The Facts of 

 Perception.' On March 2, 1881, he writes to Lipschitz : 



' I have been interested in seeing that you have hit on the 

 same train of ideas as myself in the Theory of Knowledge. 

 I am pleased, and it renews my courage, although I have quite 

 given up hope of living long enough to see any reformation in 

 philosophy. In my thoughts I rail against the faculty philoso- 

 phers, like Schopenhauer, but I will not put this on paper. 

 Each can only read himself, and is incapable of understanding 

 the thoughts of others. Yet when I see the mathematicians 

 and physicists gradually coming round to my ways, it at least 

 gives me hope for the future. I expected opposition as a matter 

 of course from the faculty people, who had preached the opposite 

 ideas all their lives, but I did not anticipate that after all the 

 trouble I have taken to set forth my meaning in different aspects, 

 they would only deduce the wildest misunderstandings. On 

 the other hand, I do not know how to meet (and this enrages 

 me, often as I have sworn not to get annoyed about it) the 

 calmness with which people, who are incapable of grasping 

 the simplest geometrical statement, pronounce upon the most 

 complex problems of the Theory of Space in the sure convic- 

 tion of superior wisdom. In conclusion, it would be very 

 profitable for the subject if you were to work up and publish 

 your views. It will have more weight when it gradually 

 appears that the people who have made a profound study of 

 mathematical questions are obliged as a class to judge in this 

 way. The individual, even if he be a Riemann, will always 

 be regarded as a crank who is discussing unfamiliar matters 

 as an amateur. You won't get much pleasure from it, but one 

 must bestir oneself to see that the community of right-thinking 

 persons increases gradually. At bottom it is the false rational- 

 ism and theorizing speculation that is the most crying evil of 

 our German education in all directions.' 



Helmholtz felt the necessity more and more of freeing his 

 mind from philosophical speculations, and in order not to return 

 at once to the physico-mathematical problems that had occupied 

 him for so long a time, he took up and completed certain earlier 

 physiological and electrical questions, which compelled him to 

 devote himself in the first instance to purely experimental 

 work. 



