This is a quote from the book "The Virtue Of Selfishness" by Ayn Rand
... united by means of a specific definition. Every word of man’s language, with the exception of proper names, denotes a concept, an abstraction that stands for an unlimited number of concretes
of a specific kind. It is by organizing his perceptual material into concepts, and his concepts into wider and still wider concepts that man is able to grasp and retain, to identify and integrat
e an unlimited amount of knowledge, a knowledge extending beyond the immediate perceptions of any given, immediate moment. Man’s sense organs function automatically; man’s brain integrates h...
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