Another very interesting point is Spencer’s physiological vindication of profit. The limbs, glands, or other members of an animal are developed by exercise. But in order “that any organ in a living being may grow by exercise, there needs to be a due supply of blood.” All action implies waste; blood brings the materials for repair; and before there can be growth, the quantity of blood supplied must be more than is requisite for repair. “In a society it is the same. If to some district which elaborates for the community particular commodities--say the woolens of Yorkshire--there comes an augmented demand; and if in fulfillment of this demand, a certain expenditure and wear and tear of the manufacturing organization are incurred; and if, in payment for the extra quantity of woolens sent away there comes back only such quantity of commodities as replaces the expenditure, and makes good the waste of life and machinery; there can clearly be no growth. That there may be growth, the commodities obtained in return must be more than sufficient for these ends; and just in proportion as the surplus is great will the growth be rapid. Whence it is manifest that what in commercial affairs we call profit, answers to the excess of nutrition over waste in a living body.” This is “physiological” political economy with a vengeance and shows to what straits bourgeois apologists are reduced to find a justification of that exploitation of labor which is the only source of profit. In concluding this point Spencer seems to satirize his own position and at the same time gives something that looks very much like a socialist explanation of panics. He says: “And if in the body politic some part has been stimulated into great productivity, and afterwards can not get paid for all its produce, certain of its members become bankrupt, and it decreases in size.” The truth of the whole matter is that Spencer is wholly at sea the moment he touches political economy, and in place of some elementary knowledge on that subject, we have the obsolete theories of the Manchester School proclaimed in the name of physiology. Then follows a series of very ingenious comparisons. Following Liebig, he compares coins to blood corpuscles calling the later blood-discs to enhance the analogy and concludes: “throughout extensive divisions of the lower animals, the blood contains no corpuscles; and in societies of low civilization, there is no money.” Then the development of blood vessels in lower animals is compared to the development of roads in primitive societies; their greater perfection in higher animals comparing with the railroads which more effectively convey food stuffs to the centers of population. Amid much that is fantastic and tedious, he says: “And in railways we also see, for the first time in the social organism, a system of double channels conveying currents in opposite directions as do the arteries and veins of a well-developed animal.”