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Mark Dominus (陶敏修) mjd@pobox.com About me RSS Atom 12 recent entries My new git utility `what-changed-twice` needs a new name Mystery of the quincunx's missing quincunx The fivefold symmetry of the quince A descriptive theory of seasons in the Mid-Atlantic Claude and I write a utility program A puzzle about balancing test tubes in a centrifuge Proof by insufficient information Willie Singletary will you please go now? How our toy octopuses got revenge on a Philadelphia traffic court judge Does someone really have to do the dirty jobs? The mathematical past is a foreign country Baseball on the Moon Archive: 2025: JFMAMJ   JAS 2024: JFMAMJ   JASOND 2023: JFMAMJ   JASOND 2022: JFMAMJ   JASOND 2021: JFMAMJ   JASOND 2020: JFMAMJ   JASOND 2019: JFMAMJ   JASOND 2018: JFMAMJ   JASOND 2017: JFMAMJ   JASOND 2016: JFMAMJ   JASOND 2015: JFMAMJ   JASOND 2014: JFMAMJ   JASOND 2013: JFMAMJ   JASOND 2012: JFMAMJ   JASOND 2011: JFMAMJ   JASOND 2010: JFMAMJ   JASOND 2009: JFMAMJ   JASOND 2008: JFMAMJ   JASOND 2007: JFMAMJ   JASOND 2006: JFMAMJ   JASOND 2005: OND Subtopics: Mathematics 245 Programming 99 Language 95 Miscellaneous 75 Book 50 Tech 49 Etymology 35 Haskell 33 Oops 30 Unix 27 Cosmic Call 25 Math SE 25 Law 22 Physics 21 Perl 17 Biology 16 Brain 15 Calendar 15 Food 15 Comments disabled

Sat, 25 Aug 2012 On the consistency of PA A monk asked Li Fu, "Master, how do we know that the Peano axioms are consistent?" Li Fu said, "The axioms are consistent because they have a model." [Other articles in category /math] permanent link