THE PHYSICAL AND THE MENTAL SCIENCES 111 



the law means to us merely a generalization of routine experiences, 

 and if thus no absolute validity is attached to the law. This necessity 

 between cause and effect must thus have its ultimate reason in our 

 own understanding. We must be logically obliged to connect the 

 objects in such a way, and wherever observation seems to contradict 

 that which is logically necessary, we must reshape our idea of the 

 object till the demands of reason are fulfilled. That is, we must sub- 

 stitute for the given object an abstraction which serves the purpose of 

 a logically necessary connection. That demand is clearly not satisfied 

 if we simply group the totality of such causal judgments under the 

 single name, Causality, and designate thus all these judgments as 

 results of a special disposition of the understanding. We never under- 

 stand why just this cause demands just this effect so long as we rely 

 on such vague and mystical power of our reason to link the world by 

 causality. 



But the situation changes at once if we go still further back in the 

 categories of our understanding. While a mere demand for causality 

 never explains what cause is to be linked with what effect, the vague- 

 ness disappears when we understand this demand for causality itself 

 as the product of a more fundamental demand for identity. That an 

 object remains identical with itself does not need for us any further 

 interpretation. That is the ultimate presupposition of our thought, 

 and where a complete identity is found nothing demands further 

 explanation. All scientific effort aims at so rethinking different ex- 

 periences that they can be regarded as partially identical, and every 

 discovery of necessary connection is ultimately a demonstration of 

 identity. If we seek connections with the final aim to understand 

 them as necessary, we must conceive the world of our objects in such 

 a way that it is possible to consider the successive experiences as parts 

 of a self-identical world; that is, as parts of a world in which no sub- 

 stance and no energy can disappear or appear anew. To reach this end 

 it is obviously needed that we eliminate from the world of objects all 

 that cannot be conceived as identically returning in a new experience; 

 that is, all that belongs to the present experience only. We do elimin- 

 ate this by taking it up conceptually into the subject and calling it 

 psychical, and thus leaving to the object merely that which is con- 

 ceived as belonging to the world of everybody's experience, that is, of 

 over-individual experience. The whole history of natural science is 

 first of all the gigantic development of this transformation, resolution, 

 and reconstruction. The objects of experience are re-thought till 

 everything is eliminated which cannot be conceived as identical with 

 itself in the experiences of all individuals and thus as belonging to the 

 over-individual world. All the substitutions of atoms for the real thing, 

 and of energies for the real changes, are merely conceptional schemes 

 to satisfy this demand. 



