This is a quote from the book "The Virtue Of Selfishness" by Ayn Rand
...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
an be seen in the rare, freak cases of children who are born without the capacity to experience physical pain; such children do not survive for long; they have no means of discovering what can i
njure them, no warning signals, and thus a minor cut can develop into a deadly infection, or a major illness can remain undetected until it is too late to fight it.
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