E1P11D3
Demonstration — Part I
Latin
Posse non existere impotentia est et contra posse existere potentia est (ut per se notum). Si itaque id quod jam necessario existit, non nisi entia finita sunt, sunt ergo entia finita potentiora Ente absolute infinito atque hoc (ut per se notum) absurdum est; ergo vel nihil existit vel Ens absolute infinitum necessario etiam existit. Atqui nos vel in nobis vel in alio quod necessario existit, existimus (vide axioma 1 et propositionem 7). Ergo Ens absolute infinitum hoc est (per definitionem 6) Deus necessario existit. Q.E.D.
English (Elwes 1883)
The potentiality of non--existence is a negation of power, and contrariwise the potentiality of existence is a power, as is obvious. If, then, that which necessarily exists is nothing but finite beings, such finite beings are more powerful than a being absolutely infinite, which is obviously absurd; therefore, either nothing exists, or else a being absolutely infinite necessarily exists also. Now we exist either in ourselves, or in something else which necessarily exists (see Axiom. i. and Prop. vii.). Therefore a being absolutely infinite--in other words, God (Def. vi.)--necessarily exists. Q.E.D.
Modern English
Being able not to exist is a lack of power; being able to exist is a power. This is self-evident. So if what now necessarily exists is nothing but finite beings, then finite beings are more powerful than an absolutely infinite being. That too is self-evidently absurd. Either nothing exists, then, or an absolutely infinite being also necessarily exists. But we ourselves exist, whether in ourselves or in something else that necessarily exists (E1A1) and (E1P7). Therefore an absolutely infinite being, that is, God (E1D6), necessarily exists. Q.E.D.