In the world of Supply and Demand the money that one group of people are willing to spend for something is equal to the amount of Money another group of  people are willing to provide (sell) that something.  The something can be anything, either goods (a product) or services.  Money is identical to the time of Employed men times their Wage rate as that is exactly what one can buy with money.  The production of that something in a physical facility has dimensons, like the Radius of a spherical tank brewing beer, and the quantity of beer or its Volume is proportional to the Radius raised to the power of the number of dimensions.  In this case V=R^(N)=R^(3), since the number of dimensions is 3.  In general, the economy is evolving, that is, it is a function of Time.  The rate of change with time for the variable, say Employed is dE/dT, and Radius  is dR/dT.  The behavior of people when it comes time to change supply and demand is defined as Garnett’s Minimization Law:

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“People minimize their time per unit of dimension, namely d((dE/dt) / (dR/dT))/dT  = zero = 0 .

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The result is that the Log(Money)=(1/N)*Log(Volume).  Also,

Log(Price)=(1/N-1)*Log(Volume)

and other relationships that can be worked out from Money=Price*Volume=Wages*Employed=Wealth+Costs,

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and the fact that demand is frequently exponential with time.