This is a quote from the book "The Virtue Of Selfishness" by Ayn Rand
...the faculty of sensation, which is sufficient to direct their actions and provide for their needs. A sensation is produced by the automatic reaction of a sense organ to a stimulus from the outsi
de world; it lasts for the duration of the immediate moment, as long as the stimulus lasts and no longer. Sensations are an automatic response, an automatic form of knowledge, which a consciousn
ess can neither seek nor evade. An organism that possesses only the faculty of sensation is guided by the pleasure -pain mechanism of its body, that is: by an automatic knowledge and an automati...
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