1 pound note of 1955-60. These words date back to goldsmiths' notes of the 17th century. When Britain left the gold standard in 1931 the words ceased to have any significance.

Karl Marx from a 100 Mark note of the German Democratic Republic, 1975.

Money as we know it represents many forms of payment. In the beginning trade and barter with natural objects was the only form of payment. With the development of a third object equal to the value of the agreement in question accepted by both participants as a means of payment, a primitive form of money was founded. This kind of money originally had the function of jewelry or a status object. Eventually this form got away from it's social context when it became a measure for the worth and price of services, work or rents. Other than actual cash there today many forms of payment. Why is the effectiveness of money believed? Is money not fiction? Does it not represent a material worth that is nonexistent?
 

US Government Mint Monetarism
Function Theories
Fiction Greshams Law
Monetary Policy Currency
Inflation  

At the height of the middle ages in the 13th and 14th century, scholars busied themselves with the theory of money. Thomas von Aquin (1225-1274) who studied the development and function of money, wrote the book "De regimine principium" (About the Principle of Rule). Nicholas Oresmius (1320-1382) wrote in his "Tractatus de origine, iue nec non et mutationibus monetarum" (Traktat on the Origins, Law and about the Change of Money) about the affects money had on history and society.
 
As time went on different and controversial theories developed.In the 19th century Karl Marx (1818-1883) created a theory that analyzed the entity and origin of money in his books "Das Kapital" and "Zur Kritik der politischen Ökonomie" (A Critique on the Political Economy). His later "Historischer und Dialektischer Materialismus" (Historical and Dialectical Materialism) became the basis of his Marxist Theory.