In the following pages the writer has made the attempt to construct a skeleton of Political Economy upon the basis of purely physical laws, and thus to obtain for its conclusions that absolute certainty which belongs to the positive sciences. The casual association of its teaching with moral philosophy, is the circumstance to which is to be attributed that metaphysical bias, manifested by almost all Economical writers, in their method of investigation, and which has conducted them to such vague, hypothetical, and unsatisfactory results. It has, indeed, been made matter of set purpose to confine its examination of the laws of the production of the objects which constitute wealth, to "such of them as are laws of the human mind;" as may be seen by consulting the Essay of Mr. J. S. Mill "On the Definition of Political Economy, arid the method of Investigation proper to it." The issue, nevertheless, has been, that grossly material estimation of man, which disregards all that is truly human in his nature, and has brought upon Political Economy, thus worked out, the name of the Dismal Science.
Mr. Henry C. Carey led the way, in the better method, by his conclusive refutation of the theory of Ricardo in regard to the occupation of land, which, for more than forty years, has been dominant with the English Economists. This fiction was an inference as to a physical fact, from "laws of the human mind," and was for that long period accepted as a fact, without a single Economist, before Mr. Carey, thinking it worth while to test its accuracy by direct observation.