[FOM] Truth and set theory

[Michael Kremer]

Panu Raatikainen asks about definability of truth for Z and ZF in NBG-.

A pair of fairly recent articles discusses some closely related matters:

DeVidi, D. and G. Solomon 1999: "Tarski on 'Essentially Richer' 
Metalanguages". /Journal of Philosophical Logic/, 28, pp. 1–28.

and the reply Ray, G. "On the Matter of Essential Richness", /Journal of 
Philosophical Logic/ 34 (2005): 433-457.

I especially recommend the second as it clears matters up very nicely.

--Michael Kremer