Didascalicon, Book II: the sciences, their parts and their discipline
Chapter XVII. On physics
Physics considers by investigation the causes of things in their effects and the effects in their causes: whence the trembling of the lands; why the deep seas swell.
(Virgil, Georgics, book II.) The powers of herbs, the angers and minds of wild beasts: every kind of shrub, also of stones and creeping things.
Physis is interpreted nature, whence also in the division of the theoretical given above Boethius called physics natural. This is also called physiology, that is, discourse about natures, which looks to the same cause. Physics is sometimes taken broadly as equivalent to the theoretical; according to which acceptation some divide philosophy into three parts, that is physics, ethics, logic; in which division the mechanical is not contained, but philosophy is restricted to physics, ethics and logic.