HAECKEL'S PHILOSOPHY. 413 



Spinoza and Newton 200 years ago, or Kant and Goethe 100 years ago. Yes, 

 we must even confess that the real essence of the substance becomes more won- 

 derful and mysterious the more deeply we penetrate into the knowledge of its 

 attributes, matter and energy, the more thoroughly we become acquainted with 

 its numberless manifestations and their evolution. What is behind the know- 

 able phenomena as a ' thing in itself ' we do not know even to this day. But 

 remaining true to his general tendency to be inconsistent with himself our 

 author goes on to say : But what do we care about this mystical ' thing in 

 itself ' anyhow, when we have no means of investigating it, when we do not 

 even know clearly whether it exists or not. Let us therefore leave it to the 

 ' pure metaphysicians ' to ponder fruitlessly over this ideal ghost, and let us 

 rejoice instead as ' true physicists ' in the enormous advances which our monistic 

 philosophy of nature has actually made.* 



We see, Haeckel' s conception of substance changes like a chameleon 

 before our very eyes. We are first told that there is a thing in itself, 

 then that we do not know what it is, and finally that we do not even 

 know that it is. We are naively told that the notion of substance will 

 solve all riddles, make all things clear to us, then we are informed that 

 it is a mystery, the greatest mystery of all, and finally it vanishes into 

 thin air before our very gaze, and turns into a phantom which perhaps 

 does not even exist. After making the conception of substance do service 

 as a principle of explanation for 436 pages of his book, after having 

 employed it as the support of real attributes, space, time and energy, 

 Haeckel suddenly dismisses it as an utterly useless piece of metaphysical 

 furniture. 



But these are not the only inconsistencies in the doctrine of sub- 

 stance. We are told that substance is unknowable, that matter and 

 force are its attributes. We are told that God, the thing in itself, is 

 an intramundane being and acts in the substance as force or energy.f 

 That is, the thing in itself is force. Yes, perhaps the original hypo- 

 thetical chemical element, the prothyl, is the substance ; % perhaps the 

 world-ether is the creating god-head.§ What does all this mean? The 

 substance perhaps does not exist; the substance does exist, but is 

 unknowable ; the substance has real attributes, and we know them ; the 

 substance is energy; the substance is perhaps prothyl; the substance is 

 perhaps the world-ether. Haeckel is certainly right in his remark that 

 consistent thinking is a difficult business. 



There is another point worth noting at this place which will come 

 up again. Haeckel speaks of the mental aspect of the substance as 

 mind, thought, sensation (Empfindung), energy, moving force. This 

 is something like Schopenhauer's will, only that it is not a substance, 

 but the attribute of a substance. As an attribute distinct from the 



* ' Weltraethsel,' pp. 437ff. 

 t ' Weltraethsel,' p. 333. 

 t ' Weltraethsel,' p. 426. 

 \ ' Monismus,' pp. 1G, 37. 



