P16: From the necessity of the Divine/Universal nature there must follow infinitely many things in infinitely many modes, (i.e., everything which can fall under an infinite intellect.)

Dem.: This Proposition must be plain to anyone, provided he attends to the fact that the intellect infers from the given definition of any thing a number of properties that really do follow necessarily from it (i.e., from the very essence of the thing); and that it infers more properties the more the definition of the thing expresses reality, i.e., the more reality the essence of the defined thing involves. But since the Divine/Universal nature has absolutely infinite attributes (by D6), each of which also expresses an essence infinite in its own kind, from its necessity there must follow infinitely many things in infinite modes (i.e., everything which can fall under an infinite intellect), q.e.d.

Cor. 1: From this it follows that God/Nature is the efficient cause of all things which can fall under an infinite intellect.

Cor. 2: It follows, secondly, that God/Nature is a cause through himself and not an accidental cause.

Cor. 3: It follows, thirdly, that God/Nature is absolutely the first cause.