The following papers contain an edited version of my correspondence with Randall Holmes outlining my proof of the equiconsistency of NFU_star with ZC + Sigma_2 Replacement.

It is my intention to prepare a more polished treatment of this subject for publication in some journal.

The files are intended to be read in the following order:

  1. NFU_star2.txt
  2. letter5.pdf
  3. letter6.pdf
  4. letter7.pdf
  5. NFU_starB.txt
  6. NFU_starC2.txt

The proof that Con(NFU_star) entails Con(ZC + Sigma_2 replacement) employs Holmes' Z construction. This is exposed in my earlier paper on NFUB I have taken the opportunity to correct an erroneous proof of Lemma 2.4. in the previous version of this paper.

The following link gives a gzipped tar file of a directory containing the papers available on this page. NFU_star directory.