372 THE POPULAR SCIENCE MONTHLY.
definitions, fullness of life can be valuable only if we include in it full- ness of happiness or some cause thereof.
Those evolutionists who appeal to the ancient principle of a Nature- fitted life have apparently not sufficiently considered one thing. Sci- ence teaches what has been, but not what will be. If the " tendencies " of Nature which they think they have determined were simply laws of Nature, conditions of the inevitable occurrence of events, there would be no reason in seeking to make a moral imperative of them ; for that can not be a matter of injunction wdrich will without fail happen of itself. But if those " tendencies " are not a fate to be fulfilled with irresistible necessity, but can be antagonized, then the question arises, Why should we act according to them, and not try to counteract them ? If we were once agreed that the complete working out of those tendencies would cross all our desires and hopes, would we rec- ognize the ethic imperative of promoting them ? On the contrary, we should recognize the obligation of so far as possible preventing their realization. And we should obey the moral command to make those tendencies ours, and advance them according to our strength so far as they appear good to us ; as we also should hold a corresponding con- duct to be right without this, without regarding it as advancing natural tendencies. What we should regard as good or evil, as worth striving for or to be avoided, must present a corresponding character to our own perception ; and what that is arises out of our own nature, not out of something different from what that might be. Thus, the final decision as to what is to be striven for and what to be avoided lies in us, in our mind and will.
We observe, also, that the aspiration for what is according to Na- ture is so far from being an obvious ethical object, that the ancient Chi-istians regarded the natural as something leading to evil. The an- cient Greeks, on the other hand, premised an agreement of the two ; and so it came to pass that the former held a pessimistic and the lat- ter an optimistic view of the world. But the Greeks did not believe in the natural because it was natural, but because they thought it good ; as the Christians disbelieved in it because it appeared bad to them, and seemed to contradict their moral convictions.
We are glad to learn from the evolutionist all he can tell us of the nature of things, and of the means of reaching the object sought after by us. Of this object, however, we do not learn from a natural his- tory of the objective world, but from the study of our own hearts. It is, therefore, self-evident that the utilitarian or the ethicist, who re- gards the highest general good as the chief moral standard, will make use of all knowledge that can cast light on the way to his end. Con- sequently, he will certainly avail himself of all the facts of biology and sociology that are of importance in regard to it.
Existence is the condition of happiness. If the happiness of mill- ions of present and future living men is to be assured, then their exist-