or mental, and its results merely a question of the quantity and quality of the human labor expended. It is this labor which gives the product its value. It is by the expenditure of this labor that its value is measured. It is as the embodiment of a certain quantity-quality of human labor that the finished product is placed upon the market for sale, and it is as such that it is exchanged for another commodity, or the universal commodity—money. In making a sale or exchange the parties knowingly or unknowingly estimate the respective quantities of labor contained in the articles exchanged or in the articles sold and the price given, and if one finds them to be equal or to preponderate in his own favor he makes the bargain. The question of quality is also regarded as a question of quantity, labor of a higher nature being reduced to its simple form of ordinary average labor of which it represents a larger quantity.
It must be borne in mind, however, that, value being a social phenomenon based on social conditions and relations, it is not the labor which happens to be accidentally contained in any given commodity, as the result of some individual conditions or circumstances under which its producer worked, that gives the commodity its value, but the socially necessary labor therein contained. In other words, the value of a commodity is not derived from the particular labor actually put into its production, nor from the amount of labor actually expended upon its production, but from the amount of average human labor which it is necessary for society to expend for its production. The mere expenditure of labor on the production of any article does not make that article a commodity having exchange value. It is social expenditure of the labor, that is, its expenditure for the purposes of social production, of the production for society of things which are useful for it, that makes the article produced a commodity having exchange-value. The expenditure, therefore, in order to create value must be necessary in accordance with the social relations and conditions existing at the time the valuation is made. This in-
