This is a quote from the book "The Virtue Of Selfishness" by Ayn Rand
...�� for those living organisms which possess it — is the basic means of survival.
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The simpler organisms, such as plants, can survive by means of their automatic physical functions
. The higher organisms, such as animals and man, cannot: their needs are more complex and the range of their actions is wider. The physical functions of their bodies can perform automatically on
ly the task of using fuel, but cannot obtain that fuel. To obtain it, the higher organisms need the faculty of consciousness. A plant can obtain its food from the soil in which it grows. An anim...