For those whose interest in Ricardo has been stimulated by the ongoing trade discussion, Murray Rothbard discusses this on pp. 94-99 of Classical Economics: An Austrian Perspective on the History of Economic Thought, vol. II (Cheltenham, UK: Edward Elgar, 1995), arguing on the basis of new research by William O. Thweat, that Ricardo made no real contribution to trade theory at all, and that the real brains behind the concept of the law of comparative advantage was James Mill and his Commerce Defended (1808).
