It is impossible to grasp the meaning of the idea of sound money if one does not realize that it was devised as an instrument for the protection of civil liberties against despotic inroads on the part of governments. Ideologically it belongs in the same class with political constitutions and bills of rights.
The demand for constitutional guarantees and for bills of rights was a reaction against arbitrary rule and the nonobservance of old customs by kings. The postulate of sound money was first brought up as a response to the princely practice of debasing the coinage.
It was later carefully elaborated and perfected in the age which--through the experience of the American continental currency, the paper money of the French Revolution and the British restriction period--had learned what a government can do to a nation's currency system.
Ludwig von Mises
in A Theory of Money and Credit, Ch. 21 (1952)
