This is a quote from the book "The ​Virtue Of Selfishness" by Ayn Rand
...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.
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“Sacrifice” is the surrender of a greater value for the sake of a lesser one or of a nonvalue. Thus, altruism gauges a man’s virtue by the degree to which he surrenders, renounces
or betrays his values (since help to a stranger or an enemy is regarded as more virtuous, less “selfish,” than help to those one loves). The rational principle of conduct is the exact oppos...
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