1p8d.md (478B)
1 There can only be one substance with an identical 2 attribute, and existence follows from its nature (Prop. vii.); 3 its nature, therefore, involves existence, either as finite or 4 infinite. It does not exist as finite, for (by Def. ii.) it 5 would then be limited by something else of the same kind, which 6 would also necessarily exist (Prop. vii.); and there would be 7 two substances with an identical attribute, which is absurd 8 (Prop. v.). It therefore exists as infinite. Q.E.D. 9 10