If works upon Political Economy, representing the orthodox European doctrine, are to be written, John Stuart Mill is certainly the man to write them. Able, candid, judicial, indefatigable, powerfully poised,--characterized by remarkable mental amplitude, by a rare steadiness of brain, by an admirable sense of logical relation, by a singular ease of command over his intellectual forces, by a clear and discriminating eye that does not wink when a hand is shaken before it,--of a humane and widely related nature, whose heats lie deep, so deep that many may think him cold,--of an understanding as dry as John Locke's, wanting imagination in all its degrees, from rhetorical imagination, which is the lowest, to epic imagination, which is the highest, and therefore destitute of the sovereign insights which go only with this faculty in its higher degrees, while, on the other hand, freed from the enticements and attractions that are inseparable from it,--Mr. Mill has qualifications unsurpassed, perhaps, by those of any man living for considerate and serviceable thinking upon matters of immediate practical interest and of a somewhat tangible nature. His mental structure exhibits combinations which are by no means frequent. Seldom is seen a conjunction of such cold purity of thinking with such generosity of nature; seldom such considerateness, such industry, patience, and carefulness of deliberation, with a boldness so entire; seldom such ducal self-possession and self-sufficingness, with equal openness to social and sympathetic impression; nor less rare, perhaps, is the union of a reflective power so large and dominating with an observation so active. These mental qualities fit him in a peculiar degree for service in the field of Political Economy as now commonly defined,--a branch of literature which, more, perhaps, than any other, represents at once the genius and the limitation of our time. Political Economy is a half-science, not total or integral; and if it pretend to spherical completeness, as it often does, it becomes open to grave accusation. The charges against it, considered as a strict and complete science, are two.