Excerpt from Two Lectures on Political Economy, Delivered at Clinton Hall, Before the Mercantile Library Association of the City of New York, on the 23d and 30th of December, 1831 But to talk of a theory, as opposed to practice, is a gross perversion of language, and a contradiction in terms. A theory or science is only a history of practice; it is a collection of experiments arranged in order and accompanied by an analysis to unveil their causes and effects, and unless it accords with the results of observation, and bears the test of experience, it is altogether worthless, while, on the other hand, "without principles deduced from analytical reasoning, experience is a useless and a blind guide." There is no proposition however absurd, which statistical data may not be brought to sustain; but it is the part of science to distinguish between unconnected events, and those which succeed one another as cause and effect. We have, indeed, an ample illustration of the consequence of deducing inferences from isolated facts in the appeals made to political arithmetic by both the friends and opponents of the protecting system. On the one side, the falling off in the price of most manufactured commodities, which is common to us and to Europe, and is to be ascribed to the change in the currency, increased facilities of obtaining the raw material, improvements in machinery, the altered situation of the world, and other causes, is claimed as a proof of the beneficial effects of high tariffs; on the other, the depressed condition of the old southern states, - the necessary result of bringing the virgin soil of Illinois and Alabama into competition with the worn out lands of Virginia and Carolina, is wholly imputed to the same Congressional enactments. We do not mean to contend that those who profess to act according to the doctrines of Political Economy, never commit mistakes. It very often happens, that an incorrect application is made of a principle in itself perfectly unexceptionable. A student in Natural Philosophy, regarding solely the vis inertiae of matter, and not attending to friction and other countervailing causes, might be astonished to find that a body, once put in motion, did not continue to move on for ever. About the Publisher Forgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.com This book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully; any imperfections that remain are intentionally left to preserve the state of such historical works."