This is a quote from the book "The Virtue Of Selfishness" by Ayn Rand
... no automatic guarantee of the efficacy of his mental effort.
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Nothing is given to man on earth except a potential and the material on which to actualize it. The potential is a supe
rlative machine: his consciousness; but it is a machine without a spark plug, a machine of which his own will has to be the spark plug, the self-starter and the driver; he has to discover how to
use it and he has to keep it in constant action. The material is the whole of the universe, with no limits set to the knowledge he can acquire and to the enjoyment of life he can achieve. But e...