CONFORMITY WITH PLAN 273 



For the sake of clearness, I shall now give the formute 

 for the various kinds of action, and I shall disctiss thes^ 

 afterwards. 



The reflex action = ^-MO„AO_E 



The form action = ^-^0 _AO_EI ^ 



rru • X- x- .• R MO AOI E 

 The instinctive action = -v — "= t.^ — ^^^ — ^ 



^. 1 ^. ,. R MOI AO E 

 Ihe plastic action = y — ~ T ~ T 



The action based on experience = -j- — — — ^ 



THE REFLEX ACTION 



Hitherto the reflex action =t— t ~t~t has been 



treated as a purely mechanical process, without taking into 

 account the " direction," which, here also, is going on all the 

 time. And again and again there have been attempts to 

 interpret all other actions as reflexes. This is justifiable in 

 so far that, during every action, the course of excitation in 

 an animal presupposes a flawless steering-mechanism, since 

 the transmission of excitation and its reversal are purely 

 mechanical problems. In a number of works I have pointed 

 out that, in excitation, we have to distinguish between amount 

 and pressure, and that the nervous centres have a varying 

 capacity for it. Furthermore, there are nervous arrangements 

 that can best be compared with valves. 



In spite of all this very finely elaborated detail in the 

 steering-mechanism of animals, the machine of the body, like 

 any other machine (even if its rule of working is elaborated 

 very precisely) is never in a position to go on continuously 

 without direction. Accordingly the mental image we made of 

 the body-machine is necessarily incomplete if we leave out 



S 



