With the development of civilisation, man’s wants become more various, and his aptitudes more specialised. The consequence is, that he can produce more utilities than before; but these utilities are more limited in their nature; they are all of one kind. He now produces, not so much what he wants, as what others want. Hence it comes to pass that exchange becomes an ever more imperious necessity; for exchange consists in giving away what are to us superfluous utilities in order to obtain what are to us necessary utilities.
Yves Guyot, C. H. d’Eyncourt Leppington, translator, Principles of Social Economy (1892), p. 65.
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