412 POPULAR SCIENCE MONTHLY. 



(or matter and energy) are inseparably connected.* God is not an 

 external being, acting from without, but a divine power or moving 

 spirit, the cosmos itself ; the phenomena of surrounding nature, organic 

 as well as inorganic, are merely different products of one and the same 

 original force, different combinations of one and the same original 

 matter, f All the individual objects in the world, all the individual 

 forms of existence, are merely transitory forms of the substance, acci- 

 dents or modes. These modes are corporeal things, material bodies, 

 when we consider them under the attribute of extension (as filling 

 space) ; forces or ideas, when we regard them under the attribute of 

 thought (or 'energy'). Matter (the stuff filling space) and energy 

 (the moving force) are two attributes of one substance. J 



This view Haeckel calls monism, and tries to distinguish from 

 materialism as follows: (1) Our pure monism is neither identical with 

 theoretical materialism, which denies mind and resolves the world 

 into a sum of dead atoms, nor with theoretical spiritualism (recently 

 termed Energetik by Ostwald), which denies matter and regards the 

 world as a spatially arranged group of energies or immaterial natural 

 forces. (2) Matter can never exist and act without mind, nor mind 

 without matter. 'We adhere to the pure and unambiguous monism of 

 Spinoza,' says Haeckel; 'matter, as the infinitely extended substance, 

 and mind (or energy) as the sentient (empfindend) or thinking sub- 

 stance, are the two fundamental attributes or ground properties of the 

 all-embracing divine world-being, the universal substance.' § 



If we interpret Haeckel's system in the light of the preceding state- 

 ments, we certainly reach a kind of monism. Mind and matter are 

 both aspects of an underlying substance. There is no difficulty in 

 understanding what Haeckel means by the material aspect of the sub- 

 stance: it is the space-filling, extended stuff. It is not so easy to see, 

 however, what the other phase of substance, the mental aspect, is. This 

 attribute the philosopher calls mind or Geist, thought, the sentient 

 side, energy, the moving force. In the chapter on substance we are 

 left under the impression that these attributes are not independent enti- 

 ties, but attributes of something behind them, of a thing in itself called 

 the substance. This impression is strengthened by Haeckel's concluding 

 reflections at the end of his book : 



We confess at the outset that we know just as little of the innermost 

 essence of nature to-day, as did Anaximander and Empedocles 2,400 years ago, 



* P. 23. 



t ' Monismus,' p. 13. 



t ' Weltraethsel,' pp. 249f. 



\ ' Weltraethsel,' p. 23. ' Monismus,' p. 27 : " For our monism an ' imma- 

 terial living spirit ' is as unthinkable as a ' dead spiritless matter ' ; in every 

 atom both are inseparably combined. The other systems conceive force and 

 matter as two essentially different substances." 



