Cassii iatrosophistae naturales et medicinales quaestiones LXXXIIII, circa hominis naturam & morbos aliquot

VIII. Pleasure is like a diffusion and relaxation of the body, and the sense itself bears witness to this in a certain way. It is agreed, however, that pleasure also occurs in sleep, as both experience and the poets bear witness. For he calls sleep nēdumon sweet/peaceful, as if it were hēdonēs prektikon productive of pleasure, that is, the author of pleasure. Therefore, if pleasure is a dissolution of the body and is brought about by sleep, why do we not say that sleep relaxes rather than densifies, as the Methodics a school of medicine emphasizing the 'strictum' and 'laxum' states of the body think? Indeed, navigation or being carried in a boat also relaxes the body, and through its use, sleep is invited with a certain pleasure, wherefore from this it can also be conjectured that sleep Thus Virgil: "Peaceful rest through the limbs."