saying that concentration upon one's business and service implies that one should not attempt to make money elsewhere. This concentration on one's affairs therefore grows into a sort of practical system in which each member of the business community is looking after some function or activity to the exclusion of other things. And so the world's work is carried on to the best advantage, each function being filled by those particular men who have become relatively expert therein. From this system arises a business habit or method not always understood by the young and inexperienced, by the non-business person. We refer to the practice in trade of leaving to each individual, to each enterprise, to each organization, the responsibility for looking out for its own interests when having dealings with others. _Caveat emptor_--let the buyer beware--expresses an extreme development of this, and in its common signification, that each side is to be permitted and expected to take any advantage of the other side that it may be able to secure, it describes a state of warfare rather than of business. In buying and selling, in aiming to obtain the most favorable terms for each line of his activity, in meeting conditions of competition, in all these relations, the business man is endeavoring to better himself and may doubtless be tempted here and there to forget the interests of the other party to the transaction. But to yield to such temptation would merely be to abuse a principle which on the whole is sanctioned by the requirements of economic efficiency. This principle is that the nearest approximation to effective justice in business transactions is reached when on each side the parties devote themselves to their respective interests and points of view. If _A_ has a house for sale and _B_ is a prospective buyer, the essence of the possible transaction between the two is that _A_'s idea of the value of the property is different from _B_'s idea of that value; or at any rate that _A_ sees less value in it to him than does _B_ to _B_. This is of course typical of all business transactions--the seller desires the money above the commodity, the buyer prefers the commodity to the money. The seller and the buyer each dwells naturally upon his own idea of value. This is altogether desirable, not to say indispensable, and is characteristic of every relation of business, wherever two men buy and sell, employ one another, or have other dealings together. The situation is somewhat the same as in a law suit where the duty of the attorney for the plaintiff is to make every point that fairly can be made for the plaintiff, while the attorney on the other side must correspondingly make every point that can properly be made for the defendant. Each side is supposed to look after the interest of that side. Similarly, in a business organization, say a railroad, when some new project is under consideration it will be submitted to the engineer, to the chemist, to