Full Idea
The philosophy of evolution offers us today a new criterion, which is objective and fixed, as an ethical test between right and wrong: That is to be called good which is destined to prevail or survive.
Gist of Idea
Evolution suggests prevailing or survival as a new criterion of right and wrong
Source
William James (The Sentiment of Rationality [1882], p.44)
A Reaction
Perceptive for its time. Herbert Spencer may have suggested the idea. James dismisses it, because it implies a sort of fatalism, whereas genuine moral choices are involved in what survives.
Book Reference
James,William: 'Selected Writings of William James', ed/tr. Bird,Graham [Everyman 1995], p.44