284 HERMANN VON HELMHOLTZ 



empiricism, a school which confines itself to the discovery of 

 facts, and declines to seek for any law or connexion in the facts 

 discovered. On the other hand, he was far from posing as the 

 theorist, who holds it unnecessary to obtain experimental 

 confirmation of the conclusions derived from the hypotheses 

 which he accepts as axioms. Above all he was the enemy 

 of metaphysical hypothesis, and his fear of any resurrection 

 of Hegel's ' Naturphilosophie ' may sometimes have made him 

 a sterner critic of the works of others than would otherwise 

 have been the case. 



As Helmholtz said on another occasion, ' It is unworthy of 

 a would-be scientific thinker to forget the hypothetical origin 

 of his propositions. The arrogance and vehemence with which 

 such masked hypotheses are defended are, as a rule, the usual 

 consequence of a sense of dissatisfaction which their champion 

 feels in the depths of his consciousness as to the validity of his 

 contention.' 



Helmholtz trusted that the conviction might gain ground 

 that the only successful experimenter in physical science is the 

 man who has a thorough theoretical knowledge, and knows 

 how to propose the right questions in accordance with this, 

 while, on the other hand, those only could profitably theorize 

 who had a wide practical knowledge of experimental work, 

 as had been so brilliantly demonstrated in the discovery of 

 Spectrum Analysis. In his eyes mathematical physics is also 

 an empirical science, and he endeavours in his Address to 

 break down the barrier between experimental and theoretical 

 physics. In our experience we only meet with extended and 

 composite bodies, whose actions are compounded of those of 

 the separate parts. If we would learn the simplest and most 

 general laws of interaction between the masses and substances 

 that exist in nature, as abstracted from the form, size, and position 

 of the effective bodies, we must go back to the laws of action 

 that govern continuous and homogeneous volume-elements, 

 and not to the disparate and heterogeneous atoms, so that 

 mathematical physics thus becomes as subject to the control 

 of experience as experimental physics. 



He attacks the same question of the reciprocal relations 

 between experimental and mathematical physics in his essay 

 1 On the Attempt to Popularize Science ', published in 1874 as 



