144 THE EIDDLE OF THE UNIVERSE. 



These facts of ontogeny are beyond the explanation 

 of the dualistic and mystic psychology which still 

 prevails in the schools ; whereas they find a perfectly 

 simple interpretation in our monistic philosophy. 



The physiological fact which is most material for a 

 correct appreciation of individual psychogeny is the 

 continuity of the psyche through the rise and fall of 

 generations. A new individual comes into existence 

 at the moment of conception ; yet it is not an inde- 

 pendent entity, either in respect of its mental or its 

 bodily features, but merely the product of the blending 

 of the two parental factors, the maternal egg-cell and the 

 paternal sperm-cell. The cell-souls of these two sexual 

 cells combine in the act of conception for the forma- 

 tion of a new cell-soul, just as truly as the two cell- 

 nuclei, which are the material vehicles of this psychic 

 potential energy, unite to form a new nucleus. As 

 we now see that the individuals of one and the same 

 species — even sisters born of the same parents — 

 always show certain differences, however slight, we 

 must assume that these variations were already present 

 in the chemical plasmatic constitution of the generative 

 cells themselves. 1 



These facts alone would suffice to explain the infinite 

 variety of individual features, of soul and of bodily 

 form, that we find in the organic world. As an 

 extreme, but one-sided, consequence of them, there is 

 the theory of Weismann, which considers the amphi- 

 mixis, or the blending of the germ-plasm in sexual 

 generation, to be the universal and the sole cause of 

 individual variability. This exclusive theory, which 

 is connected with his theory of the continuity of the 



1 Law of individual variation. Vide Natural History of Creation. 



