This is a quote from the book "The Virtue Of Selfishness" by Ayn Rand
...Today, a great many well- meaning, reasonable men do not know how to identify or conceptualize the moral principles that motivate their love, affection or good will, and can find no guidance in
the field of ethics, which is dominated by the stale platitudes of altruism.
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On the question of why man is not a sacrificial animal and why help to others is not his moral duty, I
refer you to Atlas Shrugged. This present discussion is concerned with the principles by which one identifies and evaluates the instances involving a man’s nonsacrificial help to others.