On Feb 7, 2011, at 3:51 PM, FERENC KOVACS wrote:
I believe this exchange of views concerns the topic of the concept of class, the paradox of set theory,
In the literature at least, the 3D/4D debate is completely independent of the paradoxes of set theory and it is, frankly, difficult to see any direct connection between the two at all. The former has to do with the identity of objects over time; the latter have to do with the proper axiomatization of the concept of set. Nowadays, the paradoxes of set theory are widely considered to have arisen through a confusion of the mathematical notion of set, understood in terms of the so-called cumulative hierarchy and axiomatized in ZF set theory, with the logical notion of class, understood as the extension of a concept.