E2P11D
Demonstration — Part II
Latin
Essentia hominis (per corollarium præcedentis propositionis) a certis Dei attributorum modis constituitur nempe (per axioma 2 hujus) a modis cogitandi quorum omnium (per axioma 3 hujus) idea natura prior est et ea data reliqui modi (quibus scilicet idea natura prior est) in eodem debent esse individuo (per axioma 3 hujus). Atque adeo idea primum est quod humanæ mentis esse constituit. At non idea rei non existentis. Nam tum (per corollarium propositionis 8 hujus) ipsa idea non potest dici existere; erit ergo idea rei actu existentis. At non rei infinitæ. Res namque infinita (per propositiones 21 et 22 partis I) debet semper necessario existere; atqui hoc (per axioma 1 hujus) est absurdum; ergo primum quod esse humanæ mentis actuale constituit, est idea rei singularis actu existentis. Q.E.D.
English (Elwes 1883)
The essence of man (by the Coroll. of the last Prop.) is constituted by certain modes of the attributes of God, namely (by II. Ax. ii.), by the modes of thinking, of all which (by II. Ax. iii.) the idea is prior in nature, and, when the idea is given, the other modes (namely, those of which the idea is prior in nature) must be in the same individual (by the same Axiom). Therefore an idea is the first element constituting the human mind. But not the idea of a non--existent thing, for then (II. viii. Coroll.) the idea itself cannot be said to exist; it must therefore be the idea of something actually existing. But not of an infinite thing. For an infinite thing (I. xxi., xxii.), must always necessarily exist; this would (by II. Ax. i.) involve an absurdity. Therefore the first element, which constitutes the actual being of the human mind, is the idea of something actually existing. Q.E.D.
Modern English
The essence of man (E2P10C) is constituted by certain modes of the attributes of God, namely, (E2A2), by modes of thinking, of all of which the idea is prior in nature (E2A3), so that when the idea is given, the remaining modes (those of which it is prior in nature) must also be in the same individual (E2A3). An idea is therefore the first thing constituting the human mind.
But not the idea of a non-existent thing: for then (E2P8C) the idea itself cannot be said to exist. It must therefore be the idea of something that actually exists. But not the idea of an infinite thing: for an infinite thing (E1P21) (E1P22) must always necessarily exist, and that (E2A1) is absurd. Therefore the first thing that constitutes the actual being of the human mind is the idea of a singular thing that actually exists. Q.E.D.