§ 7. As the maximum wage may be said to vary with productivity, so the minimum wage is said to vary with the "wants" of the worker. Women are said to "want" less than man, and therefore the stress of competition can drive their wages to a lower level. It is possible that a woman can sustain the smaller quantity of physical energy required for her work somewhat more cheaply than a man can sustain the energy required for his work, and that the early increments of material comfort above the bare subsistence line may be attended by a larger increase of productivity in the man than in the woman. If this is so, then the minimum subsistence wage and the wage of true economic efficiency, the smallest wage a wise employer in his own interest will consent to pay, are lower in the case of women than of men. But this difference furnishes no adequate explanation of the difference between the male and the female minimum wage. The wage of the low-skilled male labourer enables him to consume certain things which do not belong strictly to his "subsistence"--to wit, beer and tobacco; the wage of the low-skilled female labourer often falls below what is sufficient with the most rigid economy to provide "subsistence." We are not then concerned with a difference which refers primarily to the quantity of food, etc., required to support life. The wages of the low-skilled labourer in regular employ would, if properly used, suffice to furnish him more than a bare physical subsistence; the wages of the lowest-paid women workers in factories would not suffice to maintain them in the physical condition to perform their work.[251] It is not then precisely with the "standard of comfort" of male and female workers that we are concerned. The economic relation in which men and women workers stand to other members of their family is a more important factor. The wage of a male worker must be sufficient to support not only himself but the average family dependent upon him, in the standard of comfort below which he will not consent to work. When little work is available for his wife and children, or where his "standard of comfort" requires them not to undertake wage-work, his minimum wage must suffice to keep some four persons. His standard of comfort may be beaten down by stress of circumstances, his family may be driven to take what work they can get, but in any case his wage must be above the "subsistence" of a single man. When the man is the sole wage-earner, or is only assisted slightly by his family, as, for example, in the metal and mining and building industries, average male wages are much higher than in the textile industries, where the women and children share largely in the work.[252]