A body of public opinion must be formed, must make itself felt, and in the end transform, and be transformed by, the gradual raising of individual standards of conduct.
It is curious to see how difficult it is to make some men understand that insistence upon one factor does not and must not mean failure fully to recognize other factors.
 Theodore Roosevelt, Theodore Roosevelt; an Autobiography (1913). copy citation

Context

“Furthermore, I believe that, after all that the Government can do has been done, there will remain as the most vital of all factors the individual character of the average man and the average woman. No governmental action can do more than supplement individual action. Moreover, there must be collective action of kinds distinct from governmental action. A body of public opinion must be formed, must make itself felt, and in the end transform, and be transformed by, the gradual raising of individual standards of conduct. It is curious to see how difficult it is to make some men understand that insistence upon one factor does not and must not mean failure fully to recognize other factors. The selfish individual needs to be taught that we must now shackle cunning by law exactly as a few centuries back we shackled force by law. Unrestricted individualism spells ruin to the individual himself.” source