The Instructor 3.9.46

There are four reasons (for this is where I turned aside) for which we go to the bath: for cleanliness, warmth, health, or finally pleasure. Bathing for pleasure must be dismissed; for shameless pleasure must be cut out entirely. Women may take the bath for cleanliness and health, men for health only. Bathing for warmth is superfluous, since one can relieve in other ways what is stiffened by cold. Constant use of the bath weakens the strength and relaxes the natural tone, and often brings faintness and fainting fits. For bodies drink, in a way, like trees, not only with the mouth but also, they say, through the opening of the pores of the whole body in the bath. The proof is that people who are thirsty often relieve their thirst by getting into the water. So even if the bath is useful for something, we should not weaken ourselves by it. The ancients called baths “fullers of men,” since they wrinkle bodies sooner than is fitting and force them to age before their time, boiling them, as the flesh is softened by the heat like iron; hence, as it were for dipping