HIPPOCRATES in three words expresses the whole alimentary diet of all ages, all ranks of men, and all conditions, ὡς ὁ πονος εστι και ἡ τροφη, food should be as labour; for, as he says elsewhere, if the aliments are overcome, that is, if they are subdued by the powers of the body, they invigorate it; if they overcome it, that is, when they get the better of the digestive powers, they give rise to many bad effects: and PLUTARCH justly observes from HIPPOCRATES, that health arises from the exact equality of bodily exercise and the aliments taken. The reason is, the body by its own force makes its own juices and humours out of the aliments it uses: nor is its state the same in the robust ploughman and enfeebled doctor. Whilst the former, by incessant exercise, by breathing every day the wholesome country air, by a chearful and vacant mind, unembarrassed by perplexing meditations, and by soft slumbers continually repairs his strength, he can bear any sort of food; the salival, gastric, intestinal, and bilious liquors, elaborated to the highest perfection, thoroughly dissolve the most glutinous fat, and even salt pork hardened by smoke; the strength of the muscles of the stomach and intestines is unimpaired; they suffer nothing to stay beyond its time in their cavities; and as the aliments are digested, their remains are thrown out. How different from this is the case of the man debilitated by study! The hard bowels of the mower can digest any thing, the soft viscera of the learned or indolent are incapable of digestion; the latter therefore should maturely deliberate, what his powers are equal to, and what not. Give the labouring man thin broth, small cabbage, jellies, pullet’s flesh, or white bread; the force of the viscera and constant labour will soon digest these, he will immediately grow hungry, sweat all over, and in a short time his strength will fail him, if it be not soon repaired with fat bacon, hard cheese, and black bread. But let this food, or food of the like nature, be eaten by the weak inhabitants of cities, who are unequal to the labour of digesting it, dreadful diseases will soon arise from thence, the aliments being converted into poison. These are golden words of BOERHAAVE: “Eruditi viri (inquit) nolunt gulæ temperare, & audent eadem edere quæ rustici, verum non ferunt hunc victum; optent, aut feriari a studiis, aut a duris cibis.” “Men of learning, says he, will not live temperately; but are so indiscreet as to eat the same food that labouring men do, and which they are not able to bear; so they should wish either to be exempted from the necessity of studying, or from that of eating strong food[43],” which if they continue to live upon, there arise obstinate obstructions in the abdominal viscera.