264 HERMANN VON HELMHOLTZ 



tion the same sense-impressions of that object will always 

 obtain. (4) Existing objects alter, but we seek and find laws 

 for such alterations, i.e. concepts for them, which remain 

 themselves unaltered, but only become active, i. e. as pheno- 

 mena, so often as the same conditions of their activity recur. 

 It is by this that they are differentiated from the existence 

 of substances whose phenomenal appearance can only be 

 contemplated as dependent on the observer, that of the laws 

 of nature depending upon the changes in the existing order. 

 (5) The postulation of a law of nature entails the assurance 

 that in all future corresponding cases the phenomena will 

 conform to this law. A perfect law, which states the conditions 

 and extent of the result completely and exactly, is for our 

 knowledge an adequate reason for a certain conclusion as to 

 the result. So likewise it may be regarded objectively as force, 

 as the objectively sufficient ground for the event. (6) The 

 hypotheses of natural science are attempts to discover laws of 

 a more extended import than can be immediately deduced 

 from observation. 



' The empirically demonstrable significance of knowledge Ideas 

 are signs, which can be translated back to reality by move- 

 ments. Temporal relations alone are really equal. 



' The psychical processes that underlie the origin of knowledge. 

 . . . The source of all knowledge is the transference of what has 

 already occurred in experience to what is about to be ex- 

 perienced. Deduction of the fundamental concepts that follow 

 from the nature of comprehension, and from the presupposed 

 possibility of the complete solution of this task/ 



From this starting-point Helmholtz seeks for a connexion 

 with Kant, who had already perceived that the qualities of our 

 sensations must be determined by the idiosyncrasies of our 

 mode of conception (which was first established as unquestion- 

 able by modern physiology), but apprehended space and time 

 in the same way, since we can perceive nothing in the external 

 world without its happening at a given time and occurring 

 at a given place. Here too, Helmholtz is still with Kant un- 

 conditionally, when he defines time as the given and necessary 

 transcendental form of internal, space as the corresponding 

 form of external intuition; he further agrees with him that 

 spatial intuition is a subjective form of intuition, like the other 



