Trade is not a mere business custom, as is sometimes carelessly supposed. Only to the extent that they conform to natural Economic law can trading customs be socially beneficial or continue without developing social disaster. Many customs do enter into Trade, even as habits enter into the life of individuals--some beneficial and some vicious, some in harmony with natural law and some defiant or evasive of it. But essentially Trade is a natural expression of Economic relationships. It is consequently as dependent upon conformity to natural laws as are the physical functions of individuals. Drawing inspiration continuously from natural human impulses, giving constant and increasing satisfaction to natural human needs, bringing natural human units ever closer into a natural social whole, contributing one of the two indispensable and fundamentally effective as well as obvious natural powers and facilities for the continuous and increasing production of human satisfactions, Trade is evidently as natural to the social whole as is breathing or eating to the individual. It must therefore be as completely subject to natural law. By nature man is “a trading animal.” So it has often been said, and the saying is manifestly true. There is, however, no implication here that man is an animal only. The suggestion is that, although an animal, he is more than an animal, and that Trade develops phenomena which go to prove it. Of all animals, man only is within the jurisdiction of the natural Economic laws of Trade. What other animal than man could be correctly described, in a comprehensive sense, as “a trading animal”? Not only is this characteristic distinctive. Not only is it peculiarly human. But also, and by force of natural Economic law--not commercial custom, but those natural sequences of effect from cause to which arbitrary commercial customs must yield or come to grief,--it enables mankind, the larger man, the social man, to multiply the Economic powers of each individual of the human race. Primary among those natural laws of Trade is the thoroughly tested sequence alluded to above, that Trade multiplies productive power. It does so by inviting, requiring and developing that characteristic phenomenon of Trade which is commonly called “division of labor,” but may be distinguished best as Economic specialization.[2] This phenomenon gives to the world, gives to it as a natural effect of Trade, a productive power per capita far and away beyond the productive power of any isolated individual.