This is a quote from the book "The Virtue Of Selfishness" by Ayn Rand
...r /> The pleasure-pain mechanism in the body of man — and in the bodies of all the living organisms that possess the faculty of consciousness — serves as an automatic guardian of the organis
m’s life. The physical sensation of pleasure is a signal indicating that the organism is pursuing the right course of action. The physical sensation of pain is a warning signal of danger, indi
cating that the organism is pursuing the wrong course of action, that something is impairing the proper function of its body, which requires action to correct it. The best illustration of this c...
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