Compendium of All Natural Science

even of things manufactured, three principles are noted: the privation of that form and of those lineaments which the craftsman shall produce; the matter in which he will perform the work; and the form which will arise. But in those things which nature makes, the form is prior and more vigorous; in those things, however, which are perfected by art, on the contrary, matter has more power.

9. On the causes of natural things.

Since, therefore, every cause is a principle, now that those things which were called principles have been explained, we must proceed to the causes. Four causes of natural things are noted: Matter, Form, Efficient, and End.

10. On the formal and material cause.

Matter and form have been spoken of above. For privation, although it is a principle, is nevertheless not counted among the causes. However, although any cause whatever is a principle, it does not immediately follow that any principle is a cause. But matter and form are principles and causes, just as are the efficient and the end. Yet this is the difference: that matter and form are compared intrinsically, while the efficient and the end are compared extrinsically.

11. On the efficient cause, and on the division of efficient causes.

The efficient, therefore, is that from which the principle and beginning of any thing is taken. Now, of efficient causes, some are universal, such as God; others are particular, such as Romulus. Again, some are arranged in turn by or-