Why are the Heads of Men Hairy?

A small book (7 × 12 cm²) printed in London in the nineteenth century for The Booksellers purported to contain ‘The works of Aristotle, the famous philosopher’ and included ‘His Book of Problems’. The question and answer below is one of these problems.

Q. Why are the heads of men hairy? A. The hair is the ornanment [sic] of the head, and the brain is purged of gross humours by the growing of the hair, from the highest to the lowest, which pass through the pores of the exterior flesh, becomes dry, and converted into hair. This appears to be the case from the circumstance that in all man’s body there is nothing drier than the hair, for it is drier than the bones; and it is well known that some beasts are nourished with bones, as dogs, but they cannot digest feathers or hair, but void them undigested, being too hot for nourishment. It is answered that the brain is purged in three different ways: of superfluous watery humours by the eyes, of choler by the nose, and of phlegm by the hair.

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A good head over a pair of wooden shoes is a great deal better than a wooden head belonging to an owner whose feet are shod in calf-skin.