F. Be it so.  We are agreed, then, upon this point,—­that wealth is the mass of useful things Which we produce by labour; or, still better, the result of all the efforts which we make for the satisfaction of our wants and tastes.  These useful things are exchanged for each other, according to the convenience of those to whom they belong.  There are two forms in these transactions; one is called barter:  in this case, a service is rendered for the sake of receiving an equivalent service immediately.  In this form, transactions would be exceedingly limited.  In order that they may be multiplied, and accomplished independently of time and space amongst persons unknown to each other, and by infinite fractions, an intermediate agent has been necessary,—­this is cash.  It gives occasion for exchange, which is nothing else but a complicated bargain.  This is what has to be remarked and understood.  Exchange decomposes itself into two bargains, into two actors, sale and purchase,—­the reunion of which is needed to complete it.  You sell a service, and receive a crown—­then, with this crown, you buy a service.  Then only is the bargain complete; it is not till then that your effort has been followed by a real satisfaction.  Evidently you only work to satisfy the wants of others, that others may work to satisfy yours.  So long as you have only the crown which has been given you for your work, you are only entitled to claim the work of another person.  When you have done so, the economical evolution will be accomplished as far as you are concerned, since you will then only have obtained, by a real satisfaction, the true reward for your trouble.  The idea of a bargain implies a service rendered, and a service received.  Why should it not be the same with exchange, which is merely a bargain in two parts?  And here there are two observations to be made.  First,—­It is a very unimportant circumstance whether there be much or little cash in the world.  If there is much, much is required; if there is little, little is wanted, for each transaction:  that is all.  The second observation is this:—­Because it is seen that cash always reappears in every exchange, it has come to be regarded as the sign and the measure of the things exchanged.

B. Will you still deny that cash is the sign of the useful things of which you speak?

F. A louis[6] is no more the sign of a sack of corn, than a sack of corn is the sign of a louis.

B. What harm is there in looking at cash as the sign of wealth?

F. The inconvenience is this,—­it leads to the idea that we have only to increase the sign, in order to increase the things signified; and we are in danger of adopting all the false measures which you took when I made you an absolute king.  We should go still further.  Just as in money we see the sign of wealth, we see also in paper money the sign of money; and thence conclude that there is a very easy and simple method of procuring for everybody the pleasures of fortune.