Such being the everlasting law of human existence, the essential work of the political economist is to determine what are in reality useful and life-giving things, and by what degrees and kinds of labour they are attainable and distributable. This investigation divides itself under three great heads--first, of Wealth; secondly, of Money; and thirdly, of Riches. These terms are often used as synonymous, but they signify entirely different things. "Wealth," consists of things in themselves valuable; "Money," of documentary claims to the possession of such things; and "Riches" is a relative term, expressing the magnitude of the possessions of one person or society as compared with those of other persons or societies. The study of Wealth is a province of natural science:--it deals with the essential properties of things. The study of Money is a province of commercial science:--it deals with conditions of engagement and exchange. The study of Riches is a province of moral science:--it deals with the due relations of men to each other in regard of material possessions; and with the just laws of their association for purposes of labour. I shall in this paper shortly sketch out the range of subjects which will come before us as we follow these three branches of inquiry. SECTION I.--WEALTH. Wealth, it has been said, consists of things essentially valuable. We now, therefore, need a definition of "value." Value signifies the strength or "availing" of anything towards the sustaining of life, and is always twofold; that is to say, primarily, INTRINSIC, and, secondarily, EFFECTUAL. The reader must, by anticipation, be warned against confusing value with cost, or with price. Value is the life-giving power of anything; cost, the quantity of labour required to produce it; price, the quantity of labour which its possessor will take in exchange for it. Cost and price are commercial conditions, to be studied under the head of Money. Intrinsic value is the absolute power of anything to support life. A sheaf of wheat of given quality and weight has in it a measurable power of sustaining the substance of the body; a cubic foot of pure air, a fixed power of sustaining its warmth; and a cluster of flowers of given beauty, a fixed power of enlivening or animating the senses and heart. It does not in the least affect the intrinsic value of the wheat, the air, or the flowers, that men refuse or despise them. Used or not, their own power is in them, and that particular power is in nothing else.