This is a quote from the book "The ​Virtue Of Selfishness" by Ayn Rand
...ntal, the ineffable, the undefmable — it was not by contemplating the nonexistent — that man lifted himself from the cave and transformed the material world to make a human existence possibl e on earth.

If it is a virtue to renounce one’s mind, but a sin to use it; if it is a virtue to approximate the mental state of a schizophrenic, but a sin to be in intellectual f
ocus; if it is a virtue to denounce this earth, but a sin to make it livable; if it is a virtue to mortify the flesh, but a sin to work and act; if it is a virtue to despise life, but a sin to s...
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