Further, I think that the understanding in terms of the two ways of indicating what "exists" might be tied to the dinstinction between the apprehension of existence on an empirical level and through rational inference. Modernity favors empirical "proofs" for existence, and much of the philosophy of modernity will show this favoritism in terms of the adjudication of what is to be considered to be real. Thus, atoms and considered to exist, because empirical evidence is cited in support of this claim. Can we apprehend a metaphysical or immaterial reality– for example "God." More classical forms of philosphical discourse, even a modern like Descartes, have permitted this through rational inference. In any case, one has to them make a prudential judgement in regards to the efficacy of these rational inferences, I think John Henry Newman provides a great deal of insight in this respect with his postulations in regards to the illative sense.