Commerce and Government Considered in Their Mutual Relationship
This work is only recently translated into English but it shows that he should be held in high esteem, precisely as Rothbard wrote in his History of Economic Thought. Condillac's Commerce and Government is one of the milestones in the history of economic science, on equal footing with the works of Cantillon, Say, and Bastiat.
The ideas contained in this book not only have a strong affinity with Austrian economics, but they also had a considerable and direct impact on the development of Menger’s thought. Thus is this an important work in the history of the Austrian tradition.
The book was originally published in 1776. He already had an established international reputation as one of the most brilliant philosophers of his time. But whereas his philosophical work was widely acclaimed and is still studied today, his economic thought has been systematically neglected.
He writes here of the origin and nature of wealth, on value theory (""A thing does not have value because it costs, as people suppose; instead it costs because it has a value") and even on monetary issues as a severe critic of inflation.
"When trade is perfectly free, the quantity and the need are apparent in all the markets. Then goods put themselves at their true price, and plenty spreads equally everywhere. That is what we have proved sufficiently. But when one has once taken all freedom from trade, it is no longer possible to judge, either if there is really an imbalance between the quantity and the need, or what it is."