This is a quote from the book "The Virtue Of Selfishness" by Ayn Rand
...dgment is the means by which one must choose one’s actions, but it is not a moral criterion nor a moral validation: only reference to a demonstrable principle can validate one’s choices.
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Just as man cannot survive by any random means, but must discover and practice the principles which his survival requires, so man’s self-interest cannot be determined by blind desir
es or random whims, but must be discovered and achieved by the guidance of rational principles. This is why the Objectivist ethics is a morality of rational self-interest — or of rational self...