100 SCIENCE AND PHILOSOPHY OF THE ORGANISM 



They claim to express completely by an equation all that 

 is discoverable about any sort of phenomena constantly 

 connected. 



I cannot convince myself that such a very restricted 

 view is the right one : it is very cautious, no doubt, but it 

 is incomplete, for we have the concept of the acting " cause >: 

 in our Ego and are forced to search for applications of it 

 in Nature. On the other hand, it does not at all escape 

 me that there are many difficulties, or rather ambiguities, 

 in applying it. 



We may call the " cause ' of any event, the sum total 

 of all the constellations of facts which must be completed 

 in order that the event may occur ; it is in this meaning, 

 for instance, that the first principle of energetics applies 

 the term in the words causa aequat effectum. But, by 

 using the word only in this very general sense, we deprive 

 ourselves of many conveniences in the further and more 

 particular study of Nature. Would it be better to say that 

 the " cause " of any event is the very last change which, 

 after all the constellations necessary for its start are 

 accomplished, must still take place in order that the event- 

 may actually occur ? Let us see what would follow from 

 such a use of the word causality. We here have an animal 

 germ in a certain stage, say a larva of Echinus, which is just 

 about to form the intestine : all the internal conditions are 

 fulfilled, and there is also a certain temperature, a certain 

 salinity, and so on, but there is no oxygen in the water : the 

 intestine, of course, will not grow in such a state of things, 

 but it soon will when oxygen is allowed to enter the dish. 

 Is, therefore, oxygen the cause of the formation of the 

 intestine of echinus ? Nobody, I think, would care to say 



