Cost (irrespectively of any question of demand or supply) varies with the quantity of the thing wanted, and with the number of persons who work for it. It is easy to get a little of some things, but difficult to get much; it is impossible to get some things with few hands, but easy to get them with many.
The cost and value of things, however difficult to determine accurately, are thus both dependent on ascertainable physical circumstances.[83]
But their price is dependent on the human will.
Such and such a thing is demonstrably good for so much. And it may demonstrably be bad for so much.
But it remains questionable, and in all manner of ways questionable, whether I choose to give so much.[84]
This choice is always a relative one. It is a choice to give a price for this, rather than for that;—a resolution to have the thing, if getting it does not involve the loss of a better thing. Price depends, therefore, not only on the cost of the commodity itself, but on its relation to the cost of every other attainable thing.
Farther. The power of choice is also a relative one. It depends not merely on our own estimate of the thing, but on everybody else's estimate; therefore on the number and force of the will of the concurrent buyers, and on the existing quantity of the thing in proportion to that number and force.
Hence the price of anything depends on four variables.[85]
1. Its cost.
2. Its attainable quantity at that cost.