We do not pay for the air we breathe, although so useful to us, that we could not live two minutes without it.  We do not pay for it, because nature furnishes it without the intervention of man’s labor.  But if we wish to separate one of the gases which compose it for instance, to fill a balloon, we must take some [time and] labor; or if another takes it for us, we must give him an equivalent in something which will have cost us the trouble of production.  From which we see that the exchange is between efforts, [time and] labor.  It is certainly not for hydrogen gas that I pay, for this is everywhere at my disposal, but for the work that it has been necessary to accomplish in order to disengage it; work which I have been spared, and which I must refund.  If I am told that there are other things to pay for, as expense, materials, apparatus, I answer, that still in these things it is the work that I pay for.  The price of the coal employed is only the representation of the [time and] labor necessary to dig and transport it.

We do not pay for the light of the sun, because nature alone gives it to us.  But we pay for the light of gas, tallow, oil, wax, because here is labor to be remunerated;—­and remark, that it is so entirely [time and] labor and not utility to which remuneration is proportioned, that it may well happen that one of these means of lighting, while it may be much more effective than another, may still cost less.  To cause this, it is only necessary that less [time and] human labor should be required to furnish it.

When the water-boat comes to supply my ship, were I to pay in proportion to the absolute utility of the water, my whole fortune would not be sufficient.  But I pay only for the trouble taken.  If more is required, I can get another boat to furnish it, or finally go and get it myself.  The water itself is not the subject of the bargain, but the labor required to obtain the water.  This point of view is so important, and the consequences that I am going to draw from it so clear, as regards the freedom of international exchanges, that I will still elucidate my idea by a few more examples.

The alimentary substance contained in potatoes does not cost us very dear, because a great deal of it is attainable with little work.  We pay more for wheat, because, to produce it, Nature requires more labor from man.  It is evident that if Nature did for the latter what she does for the former, their prices would tend to the same level.  It is impossible that the producer of wheat should permanently gain more than the producer of potatoes.  The law of competition cannot allow it.

Again, if by a happy miracle the fertility of all arable lands were to be increased, it would not be the agriculturist, but the consumer, who would profit by this phenomenon; for the result of it would be abundance and cheapness.  There would be less labor incorporated into an acre of grain, and the agriculturist would be therefore obliged to exchange it for less labor incorporated into some other article.  If, on the contrary, the fertility of the soil were suddenly to deteriorate, the share of nature in production would be less, that of labor greater, and the result would be higher prices.