An early statement of the Utility Theory. Condillac made his name both with economic and with philosophical writings. His most important economic work is Le Commerce et le Gouvernement, published the same year as Adam Smith's Wealth of Nations, in which he presents his subjective theory of value.

In his theory of vrai prix [true price], Condillac proposed a theory of human history divided into two phases: progress and decline. Progress is marked by a rational use of resources; decline is precipitated by bad behaviour from the upper classes that then trickles down to the workers, encouraging excess, luxury, and false prices that harm the masses. Condillac saw the remedy to this as vrai prix, a true price created by the unimpeded interaction of supply and demand, to be achieved by complete deregulation. People would be taught to work toward their best interest in an open market through a reshaping of their perceptions. By advocating of a free market economy in contrast to the prevailing contemporary policy of state control in France, Condillac influenced classical liberal economics.

According to Goldsmiths catalogue there are at least two issues in 1776, neither of which is given precedence. This is the two-volume edition, here bound as one with separate pagination (1173). Higgs lists what is probably a ghost edition of 1772 of which there are no known copies.

Condillac took holy orders between 1733 and 1740 at Saint-Sulpice church in Paris. He was then appointed Abbot of Mureau and devoted his whole life, with the exception of an interval as a court-appointed tutor at the court of Parma, to speculative thought. In Paris he was involved with the circle of the philosopher Denis Diderot, and he developed a friendship with Rousseau that lasted to the end of his life. His writings were heavily influenced by the English philosopher John Locke.

First Edition. 2 vol. bound together. 12mo. pp. [iv], 273, [3] blank; [iv], 180, uncut. Original wrappers; worn and slightly dust soiled, spine rubbed, two discreet library stamps on title page.

Goldsmiths 1173; Einaudi 1209.