SOCIAL EVOLUTION AS A BIOLOGICAL PROCESS 251 



If human ethics is truly unrelated to beginnings found in 

 lower nature, something that has arisen by itself from 

 supernature, then we must not use the terms in ques- 

 tion except by way of analogy. If, however, nature has 

 been continuous in the working out of every department 

 of human life and human thought through evolution, 

 then the criteria of the righteousness of the acts per- 

 formed even by an Amceba may be found to be basic 

 and fundamental for ethical systems of whatever human 

 race or time. This subject remains to be discussed in 

 the final chapter, but it must be clear that we cannot 

 survey the evolutionary process by which social sys- 

 tems have come into being without dealing at the same 

 time with the origin and growth of ethical conduct as such. 



Without leaving the group of one-celled animals 

 typified by Amoeba, we find colonies of the most ele- 

 mentary biological nature, where other natural obliga- 

 tions are added to the two of greatest importance. 

 Some species of the bell-animalcule, Vorticella, provide 

 characteristic examples of these primitive compound 

 protozoa. Here the assemblage is made up of one- 

 celled individuals essentially similar to one another in 

 structure and in physiological activities ; in the latter 

 respect each one of them is like Amoeba as well. They 

 may remain together for a longer or shorter period, or 

 during their whole existence until the time of repro- 

 duction. Like the solitary protozoon, each member 

 leads a complete life in and by itself, equivalent to that 

 of every biological unit. It obeys the two great laws 

 already laid down, but in addition it seems to be required 



