360 SYMBIOGENESIS 



The main cause of sterility we have found to be lack of 

 adequate reciprocal differentiation, and we can now likewise 

 see that lack of physiological and biological reciprocity must 

 have injurious effects upon mental development, and thus form 

 an additional cause of sterility. 



The law of symbiogenesis requires species to be service- 

 able, to accumulate surpluses in order to obtain mental 

 remuneration; i.e., socially valuable experience accruing only 

 through service. Crossing per se, i.e., in the absence of contri- 

 bution to biological values, as we have seen, has no particular 

 good effects ; a truth which is now evident also so far as 

 psychological effects are concerned. The same explanation 

 applies, in my opinion, to Butler's criticism of Darwin's 

 Natural Selection theory. According to him one of Darwin's 

 weak places is his contention that there can be sustained 

 accumulation of bodily wealth, more than wealth of any other 

 kind, without experience, watchfulness and good sense pre- 

 siding over the accumulation. 



We have seen that what I have called the ancestral 

 dynamics (the original "endowment") of a species however 

 depraved it may now have become, and whatever degree of 

 design it may have been that originally entered into its com- 

 position must have been of a nature to accumulate organic 

 wealth by symbiogenetic conduct. The same factors that can 

 at the present day be seen to make for organic wealth must 

 have produced it in the past though with less complexity, and, 

 as I have already stated in the previous chapter, though the 

 consciousness involved was at first but incipient, yet the solu- 

 tion of the biological problem resolved itself from the first into 

 the establishment of bio-econoinic relations with corresponding 

 degrees of mentality and of " design." The symbiogenetic 

 explanation thus may be said to give that symmetrical perfec- 

 tion to Butler's views which Prof. M. Hartog- says they lack, 

 and this without having recourse to a teleological explanation, 

 to design of the " prescient-from-all-eternity " order, which 



