of social evolution; just as mental attributes and communal organization are inseparable, so rules of conduct arise pari passu with the origin of a biological association.  Religion and theology form the second division, which takes its origin in part from the first, for these two groups of ideas are largely concerned with the authority for right conduct and with human responsibility for taking the right attitude toward the entire visible and unseen universe.  Finally, science and philosophy are briefly treated as evolved products which include within their scope all that there is in human knowledge; for this reason they take the highest place, instead of the position below religion usually assigned to them.  At the last, having reached our final standing ground, we must look back in order that we may clearly define the lessons and ultimate values of the whole doctrine of evolution.

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Ethics is the science of duty.  It is usually restricted to an examination of purely human obligations, and to a search for the reasons why men should do certain things and refrain from committing other acts.  Like psychology and sociology, ethics began as a strictly formal and a priori system of dogmas which related to the life of cultured human beings alone.  Again, like the sciences specified, it gradually broadened its scope so as to include the conventions of races lower in the scale than the civilized peoples who only were sufficiently advanced intellectually to conceive it.  Thus the comparative method came to be employed, and in direct proportion to its use, more liberal views have developed regarding the diverse methods of thought and standards of social life and of conduct among differently conditioned peoples.  Still more important is the demonstration that human ethics as a whole, like human faculty and civilization, takes its place at the end of a scale whose beginnings can be found in lower organic nature.

Those who have followed the account of social evolution given in the preceding chapter must realize that the basic general principles of natural ethics, as contrasted with “formal” ethics, have already been discovered and formulated.  A biological association of whatever grade and degree of complexity is impossible unless biological duties are discharged.  Human ethical conduct differs from insect and protozooen ethical conduct only in the element of a participation in the process by the explicit consciousness of man that he has definite obligations to others; and this distinguishing characteristic is the direct outcome of an evolution which adds reflection and conceptual thought to a mental framework derived from prehuman ancestors.  The insect hurries about in its daily life as an animated machine, whose activities are defined by heredity; its special mode of conduct is just what nature has produced by selection from among countless other forms of living which have not had the same