Any increase of labor upon material products, either directly or indirectly, may increase ability to meet future wants, while increase of labor upon present uses of wealth may diminish ability for the future. The wealth of a community is the product of all the labors that contribute to make material nature useful. This classification is important in studying the question of productive consumption of wealth, but does not decide which gives best results. It is a serious error to assume that the worker, whose labor is directly applied to materials, gives to our wealth all its value. If several men are building a house, one may contribute as much to the building by cooking for the rest as if he worked in turn in the construction. In the same way all the household, if well ordered, aid toward the result of their united labors. The physician who shortens the illness of a farmer contributes his share toward raising the farmer’s crop. The lawyer who makes property safer, and the minister who gives stronger motives for exertion, are sharers in the force that brings the product. _Physical, mental, moral labor._—The classification of labor according to the powers employed serves to call attention to the wide range of exertions rightly classed as labor. If the exertion is chiefly muscular, labor of hands, shoulders, legs or any part of the body, it is properly called physical. If the main effort is that of the intellect in planning, inventing, contriving ways and means, or in remembering, counting or thinking of any kind, it is just as truly labor, but mental. If the chief exertion is in the good will that resists temptations, guards interests, controls violence and folly, secures order and devises liberal things for society, the labor is moral. Moral labor is often recognized in wages, faithfulness being more important in some services than in others, and paid for. Mechanical devices for promoting honesty or watchfulness may save, in part, moral labor. This view of labor helps us to see the wide range of efforts that unite in production of wealth, since all the energies of a man may be employed in his work. The successful farmer is one who makes the most of all his abilities—his muscles, his mind and his heart—and his hard work is far from being confined to his hands. The three kinds of labor are combined in some proportion in every life, but the best and most productive life his most room for hard thinking and self-control.