434 INTRODUCTION TO PHILOSOPHY OF SCIENCE 



does not mean that the law of causality is not valid for these 

 microscopic happenings." x 



What is the sense, then, Planck asks, in speaking of causal 

 relations in cases where the difficulties of observation render 

 their applications impossible? The analogue of the quan- 

 tum phenomena 2 is enlightening here. The principle of in- 

 determinacy shows the impossibility of measuring both the 

 position and the velocity of a particle with the necessary 

 accuracy. This involves the conclusion that prediction of the 

 behavior of a particle is impossible, since it depends on knowl- 

 edge of state and this can never be obtained. Now if this view 

 is combined with the operational theory, the impossibility 

 of knowledge becomes the ground for the impossibility of 

 existence; hence there is an objective indeterminism. But 

 this step Planck will not take. He insists that the difficulties 

 in the ascertainment of position and velocity of a particle 

 are due to the techniques of measurement, i.e., to the rela- 

 tion of the observer to his phenomena. They are not diffi- 

 culties of the validity of the causal principle but of the prac- 

 ticability of its application. The virtue of the principle of 

 indeterminacy is that it has shown us the importance of 

 recognizing the observer and the methods which he employs 

 in observing. More specifically, it has shown us the general 

 principle to be used in determining the applicability of a 

 causal law: "The smaller the distance between the investiga- 

 tor and the object . . . the more uncertain and fallible will 

 be the causal and scientific treatment." 3 "Laplace held 

 that if there were a super-intelligence standing entirely out- 

 side of the facts occurring in the universe, this intelligence 

 would be able to see causal relations in all happenings of the 

 world of man and nature, even the most intricate and micro- 

 scopic. It is only by aiming at this sort of distance that the 

 individual could establish the required detachment of the 

 perceiving subject from the object of his research, which we 

 have already seen to be an inevitable condition for the 



1 Ibid., p. 156. 2 The Philosophy of Physics, p. 80. 



3 Where Is Science Going?, pp. 155-156. 



