112 THE SCIENTIFIC PLAN OF THE CONGRESS 



The logically primary step is thus not the separation of the physical 

 and the psychical things plus the secondary demand to connect the 

 physical things causally; the order is exactly opposite. The primary 

 desire is to connect the real objects and to understand them as causes 

 and effects. This understanding demands not only empirical observa- 

 tion, but insight into the necessary connection. Necessary connec- 

 tion, on the other hand, exists merely for identical objects and identi- 

 cal qualities. But in the various experiences only that is identical 

 which is independent of the momentary individual experiences, and 

 therefore we need as the ultimate aim a reconstruction of the object 

 into the two parts, the one perceptional, which refers to our individual 

 experience; and the other conceptional, which expresses that which 

 can be conceived as identical in every new experience. The ideal of 

 this constructed world is the mechanical universe in which every 

 atom moves by causal necessity because there is nothing in that 

 universe, no element of substance and no element of energy, which 

 will not remain identical in all changes of the universe which are pos- 

 sibly to be expected. It becomes completely determinable by antici- 

 pation and the system of our submissions to the object can be com- 

 pletely constructed. The totality of intellectual efforts to reconstruct 

 such a causally connected over-individual world of objects clearly 

 represents a unity of its own. It is the system of physical sciences. 



The physical universe is thus not the totality of our objects. It is a 

 substitution for our real objects, constructed by eliminating the indi- 

 vidual parts of our objects of experience. These individual parts are 

 the psychical aspects of our objective experience, and they clearly 

 awake our scientific interest too. The physical sciences need thus as 

 counterpart a division of mental sciences. Their aim must be the same. 

 We want to foresee the psychical results and to understand causally 

 the psychical experience. Yet it is clear that the plan of the mental 

 sciences must be quite different in principle from that of the sciences 

 of nature. The causal connection of the physical universe was ulti- 

 mately anchored in the identity of the object through various experi- 

 ences; while the object of experience was psychical for us just in so 

 far as it could never be conceived as identical in different phases of 

 reality. The psychical object is an ever new creation; my idea can 

 never be your idea. Their meaning may be identical, but the psych- 

 ical stuff, the content of my consciousness, can never be object for 

 any one else, and even in myself the idea of to-day is never the idea 

 of yesterday or to-morrow. But if there cannot be identity in different 

 psychical experiences, it is logically impossible to connect them 

 directly by necessity. If we yet want to master their successive 

 appearance, we must substitute an indirect connection for the direct 

 one, and must describe and explain the psychical phenomena through 

 reference to the physical world. It is in this way that modern psycho- 



