This conclusion, which could hardly fail to be formed merely from a view of the subjects about which political economy is conversant, is further strengthened by the differences of opinion which have prevailed among those who have directed a large share of talent and attention to this study.
During the prevalence of the mercantile system, the interest which the subject excited was confined almost exclusively to those who were engaged in the details of commerce, or expected immediate benefit from its results. The differences which prevailed among merchants and statesmen, which were differences rather in practice than principle, were not calculated to attract much attention. But no sooner was the subject raised into a science by the works of the French Economists and of Adam Smith, than a memorable schism divided, for a considerable time, the students of this new branch of knowledge, on the fundamental questions—What is wealth? and from what source or sources is it derived?
Happily for the interests of the science and its usefulness to society, the Economists and Adam Smith entirely agreed on some of those great general principles which lead to the most important practical conclusions; such as the freedom of trade, and the leaving every person, while he adheres to the rules of justice, to pursue his own interest his own way, together with some others: and unquestionably their agreement on these principles affords the strongest presumption of their truth. Yet the differences of the Economists and Adam Smith were not mere differences in theory; they were not different interpretations of the same phenomena, which would have no influence on practice; but they involved such views of the nature and origin of wealth, as, if adopted, would lead, in almost every country, to great practical changes particularly on the very important subject of taxation.
Since the æra of these distinguished writers, the subject has gradually attracted the attention of a
