4 MIND IN EVOLUTION CHAP. 



lowest Rhizopods, which must either have remained nearly 

 unchanged through many geological periods, or represent 

 a process of degradation equal in extent and scope to that 

 of their previous evolution. But indeed there is nothing 

 in the physical conditions of Evolution to imply the 

 necessity of perpetual change. The fundamental fact of 

 Evolution is that through differentiation multiplication be- 

 comes easy. Ten beings requiring precisely the same food 

 would have much less chance of supporting themselves in 

 a given space than the same number feeding on different 

 things. Thus, if one of the ten develops a liking for food 

 of a different kind, the pressure on the others is lightened, 

 and their chance improved. If we apply this to variation 

 in a species, we see that, while its first effect will be very 

 adverse to the old stock, the future consequences may be 

 quite different. It may be that by striking out a fresh 

 line the variation relieves the old type from the pressure of 

 competition. Its reduced numbers find means of subsist- 

 ence again, and increase finally to their old point. Espe- 

 cially in social evolution, however rapid the rate of change, 

 we constantly find, if we look for them, survivals of the 

 primitive type. The small general shop is not utterly ex- 

 tinguished by the mammoth store. The village cobbler 

 remains, even if it be only to botch the boots that are 

 made at a Leicester factory. So also do the Protista sur- 

 vive, and there is not the slightest reason to suppose that 

 they are passing away. Many of them indeed in the 

 form of disease-germs wage an equal struggle with the 

 lords of creation. The tendency of biological evolution in 

 general is not to produce the highest type, but rather to 

 produce as many types as possible, filling in all the lacunae 

 of organic possibility, not necessarily destroying any but 

 those which have not the character of their own kind in 

 sufficient strength. Evolution tends to space out the types 

 that it suffers, to cut them deep and true. It multiplies 

 and it defines, but it does not necessarily elevate. 



4. We have spoken already of at least one upward line 

 in the evolutionary tree. Can we trace this line ? Is there a 

 development in the true sense ? Is there progress, or the evo- 

 lution of a higher type ? To answer these questions, we must 



