8 ANTS AND SOME OTHER INSECTS. 



the visual and tactile sensation, which a uniform, low, tuning-fork 

 vibration produces on our three corresponding senses. Neverthe- 

 less, we may infer inductively that it is the same reality, the same 

 vibration which is symbolised for us in these three qualitatively 

 and totally different modes; i. e., produces in us these three differ- 

 ent psychical impressions which cannot be transformed into one 

 another. These impressions depend on activities in different parts 

 of the brain and are, of course, as such actually different from one 

 another in the brain. We speak of psycho-physiological identity 

 only when we mean, on the one hand, the cortical neurocyme which 

 directly conditions the conscious phenomena known to us, on the 

 other hand, the corresponding phenomena of consciousness. 



And, in fact, a mind conceived as dualistic could only be de- 

 void of energy or energy-containing. If it be conceived as devoid 

 of energy (Wasmann), i. e., independent of the laws of energy, 

 we have arrived at a belief in the miraculous, a belief which coun- 

 tenances the interference with and arbitrary suspension of the laws 

 of nature. If it be conceived as energy-containing, one is merely 

 playing upon words, for a mind which obeys the law of energy is 

 only a portion of the cerebral activities arbitrarily severed from its 

 connections and dubbed " psychic essence," only that this may be 

 forthwith discredited. Energy can only be transformed qualita- 

 tively, not quantitatively. A mind conceived as dualistic, if sup- 

 posed to obey the law of energy, would have to be transformed 

 completely into some other form of energy. But then it would no 

 longer be dualistic, i. e., no longer essentially different from the 

 brain-activities. 



Bethe, Uexkull, and others would require us to hold fast to 

 the physiological method, because it alone is exact and restricts it- 

 self to what can be weighed and measured. This, too, is an error 

 which has been refuted from time immemorial. Only pure mathe- 

 matics is exact, because in its operations it makes use solely of 

 equations of abstract numbers. The concrete natural sciences can 

 never be exact and are as unable to subsist without the inductive 

 method of inference from analogy as a tree without its roots. Bethe 

 and Uexkull do not seem to know that knowledge is merely rela- 



