Appendix 46.

(1035) [Being in potency and in act]

Above all, Cardinal di Cusa's book, De apice theoriae, should be read. Tommassini drew upon Ficino in support of his opinions. Both held the following doctrine, in full agreement with mine: 'Being shines so brilliantly that it is impossible to think it does not exist - other things are known through being, but being is known through itself' (Tommass., Tract. De Deo Deique propriet., bk. 1, c. 14, art. 1). Cardinal Gerdil expresses the same opinion in his well-known work against Locke and in defence of Fr. Malebranche. But the thing that has escaped all these authors is, it seems to me, the great distinction between being in potency (idea, essence of being) and being in act (cf. 530 ss.). St. Thomas uses this distinction to show that God is not among things known through themselves (S.T., 1, q. 2, art. 1). What these authors are saying is, 'Being cannot be thought without being. Therefore being exists.' Here the word 'being' is equivocal: if it means ideal being, this certainly cannot be thought unless it is and is necessarily, but it must not be confused with subsistent being. There is however a true, profound element in Ficino's and Tommassini's reasoning, which is also that of Descartes and St. Anselm. Traces of it can also be found in St. Augustine and many other ancient authors. But I will discuss this argument in the right place.