2. Preparatory to taking up the philosophical account, a few words on the use of the terms labor and value are pertinent. The word _labor_, now as formerly, denotes really two distinct, though related, things. One is the _productive power_ of human beings. For instance, labor and natural agents are called factors in production, or it is said that the entrepreneur purchases labor. The other is the _disutility_ or _discomfort_ endured by men in the course of production, as in the sentence: “This article has cost me much labor.”[13] Productive power may be accompanied by no disutility, or by moderate or high disutility, according to circumstances. Labor is used in both senses by Adam Smith. As for the word _value_, Smith explains at the outset that the term has two meanings, “value in use” and “value in exchange,” and restricts his investigations to the principles of the “exchangeable value.” This is defined as the “power of purchasing other goods” which an object “conveys” to its owner.[14] But Adam Smith does not explain nor appear to realize that he uses the term “exchangeable value” in two senses. When he asserts that the “real worth” of anything to a man “is the toil and trouble which it can save himself, and which it can impose on other people,” and that therefore labor is the real measure of the “exchangeable value of all commodities;” “exchangeable value” means something other than mere purchasing power. Writing nearly a century later, Menger said that value is that significance (_Bedeutung_) which a good attains in our estimation when we feel the satisfaction of some want to be _conditioned_ upon it. This is “_esteem_ value,” or value as _Bedeutung_. Smith’s concept, of value as “real worth,” which he has miscalled “exchangeable” value, is something analogous to this. But Smith finds the significance in labor instead of in satisfaction.[15] 3. Turning now directly to the “philosophical” account, we find the multiplicity of Adam Smith’s explanations of value illustrated once more by the fact that within this chapter he suggests two distinct labor standards. One is given as a _regulator_ of value, a something which quantitatively governs value. The other is merely a _measure_ of value. There is no adequate discussion of the mutual relations of the two. Both appear in the following sentence: “What everything is worth to the man who has acquired it, and who wants to dispose of it or exchange it for something else, is the toil and trouble which it can save to himself, and which it can impose on other people.”[16] The “toil” saved “to himself” must be the labor cost of reproduction, not distinguished by Smith from cost of production. The two standards are asserted separately. In an early and rude state of society, “the proportion between the quantities of labour necessary for acquiring different objects seems to be the only circumstance which can afford any rule for exchanging them for one another.”[17]