In contradiction to the opinion of Adam Smith, M. Say, in the fourth chapter, speaks of the value which is given to commodities by natural agents, such as the sun, the air, the pressure of the atmosphere &c., which are sometimes substituted for the labour of man, and sometimes concur with him in producing.3
But these natural agents, though they add greatly to value in use, never add exchangeable value, of which M. Say is speaking, to a commodity: as soon as by the aid of machinery, or by the knowledge of natural philosophy, you oblige natural agents to do the work which was before done by man, the exchangeable value of such work falls accordingly. If ten men turned a corn mill, and it be discovered that by the assistance of wind, or of water, the labour of these ten men may be spared, the flour, which is the produce of the work performed by the mill, would immediately fall in value, in proportion to the quantity of labour saved; and the society would be richer by the commodities which the labour of the ten men could produce, the funds destined for their maintenance being in no degree impaired.
M. Say accuses Dr. Smith of having overlooked the value which is given to commodities by natural agents, and by machinery, because he considered that the value of all things was derived from the labour of man; but it does not appear to me, that this charge is made out; for Adam Smith no where undervalues the services which these natural agents and machinery perform for us, but he very justly distinguishes the nature of the value which they add to commodities—they are serviceable to us, by increasing the abundance of productions, by making men richer, by adding to value in use; but as they perform their work gratuitously, as nothing is paid for the use of air, of heat, and of water, the assistance which they afford us, adds nothing to value in exchange. In the first chapter of the second book, M. Say himself gives a similar statement of value, for he says that "utility is the foundation of value, that commodities are only desirable, because they are in some way useful,