This is a quote from the book "The Virtue Of Selfishness" by Ayn Rand
...ge of the immediate moment. Man has to project his goals and achieve them across a span of time; he has to calculate his actions and plan his life long-range. The better a man’s mind and the g
reater his knowledge, the longer the range of his planning. The higher or more complex a civilization, the longer the range of activity it requires — and, therefore, the longer the range of co
ntractual agreements among men, and the more urgent their need of protection for the security of such agreements.
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Even a primitive barter society could not function if a man agreed...