… is from page 59 of F.A. Hayek’s brilliant 1945 lecture “Individualism: True and False,” as this essay is reprinted in Studies on the Abuse & Decline of Reason, Bruce Caldwell, ed. (2010), which is volume 13 of the Collected Works of F.A. Hayek (original emphases):
This is the constitutional limitation of man’s knowledge and interests, the fact that he cannot know more than a tiny part of the whole of society and that therefore all that can enter into his motives are the immediate effects which his actions will have in the sphere he knows. All the possible differences in men’s moral attitudes amount to little, so far as their significance for social organization is concerned, compared with the fact that all man’s mind can effectively comprehend are the facts of the narrow circle of which he is the center; that, whether he is completely selfish or the most perfect altruist, the human needs for which he can effectively care are an almost negligible fraction of the needs, of all members of society. The real question, therefore, is not whether man is, or ought to be, guided by selfish motives but whether we can allow him to be guided in his actions by those immediate consequences which he can know and care for or whether he ought to be made to do what seems appropriate to somebody else who is supposed to possess a fuller comprehension of the significance of these actions to society as a whole.