This is a quote from the book "The Virtue Of Selfishness" by Ayn Rand
...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
is sense data into percepts automatically; but the process of integrating percepts into concepts — the process of abstraction and of concept-formation — is not automatic.
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