I gave the following argument:
We have the concept true proposition. This concept is either instantiated, or it is not. If it is not instantiated, then it is true that it is not instantiated, which implies that the concept true proposition is instantiated. If, on the other hand, the concept in question is instantiated, then of course it is instantiated. Therefore, necessarily, the concept true proposition is instantiated, and there necessarily exists at least one truth, namely, the truth that the concept true proposition is instantiated.
A reader asks: Does not your argument presuppose that "to be instantiated" means "to exist extra-mentally"? What if someone believed that esse est percipi? If your argument was based on the aforementioned assumption, then would not it beg the question because it presupposes what needs to be demonstrated?
Let us first note that it cannot be coherently maintained that to be is to be perceived without qualification. To be perceived is to be perceived by someone or something. For Bishop Berkeley, the someone in question is God whose being is precisely not identical to his being perceived. The slogan therefore does not apply to God. If absolutely everything were such that its being were its being perceived, then a vicious infinite regress would arise. To put it figuratively, the world cannot be mere percepts 'all the way down.' You have to come eventually to something whose being is in excess of its being perceived.
Perhaps what the reader is getting at is that any true proposition that instantiates the concept true proposition is true only for a mind, and not true absolutely. But this too leads to an infinite regress which appears to be vicious. For consider the proposition *Every truth is true-for some mind or other; no truth is true absolutely.* Call this proposition 'P.' Is P true? No, it is true-for some mind or other. Call that proposition P*. Is it true? No, it is true-for some mind or other. An infinite regress arises, and it appears to be vicious.