Thus we are brought again and again from differing points of view to the "two renderings" as central and determinative in Value, and also more specifically to the "two efforts" of persons rather than any free contribution of Nature as constituting that portion of the compound Utility, whose function it is to gratify the "two desires" that precede the realization of Value,--that portion of the utility in any rendering that must be _compensated for_ by the other rendering. Now in order to reach in a moment more our final definition of "Value," a definition, it is believed, that will cover all the cases and take the life out of endless disputes, we need a scientific term to carry easily and exactly the meaning of any economic _rendering_. Let that word be SERVICE. We must have it in its generalized meaning, to cover the renderings of all the three kinds, in distinction from the term "personal services," which we have already used and shall continue to use to designate one class only of things exchanged, in contradistinction to "commodities" and to "credits," the other two classes. VALUE IS THE RELATION OF MUTUAL PURCHASE ESTABLISHED BETWEEN TWO SERVICES BY THEIR EXCHANGE. We offer this definition of "Value" to our readers in much confidence, that they will find it exact and adequate and altogether trustworthy. No one of them, however, is precluded from attempts to improve it in breadth and brevity and beauty; and all are invited to pick logical flaws in it, whether of ambiguity or superfluity or deficiency. Many minds and many hands in many lands have left their impress on parts of this definition, for example, Aristotle in Greece and Bastiat in France and Macleod in Great Britain; the present writer thinks, that he has bettered the definition of Bastiat, namely, "_Value is the relation of two services exchanged_," by precisely _defining_ the relation as one of mutual purchase; and he is sure, that he has improved the definition of Macleod, namely, "_The value of any economic quantity is any other economic quantity for which it can be exchanged_," by making his definition at once more abstract and more general and more definite, and also by escaping the slight implication in the word, "quantity," that only material things are exchanged in economics.