20000110 January 10th, 1999 Minor corrections (Near trivial) to the trivial systems.
19991201 December 1st, 1999 Added Chellas's axioms C, R, M[L(p&q)>(Lp&Lq)], and N. Added systems E, M(EM), EC, EN, and EK4. Updated system K.
19991130 November 30th, 1999 Added some information to K4, KD4, and S4.
19990802 August 2nd, 1999: An HTML tool applied to the directory found several dangling links. Fixed.
19990724 July 24th, 1999:
At the moment my efforts have been side tracked to the Cave Surveying pages, so no changes are happening here at the moment. I hope to get back to these by mid September.
19990705 July 5th, 1999:
Trying to keep a consistent naming is difficult, since differing authors have differing names for axioms and rules. In the past I've followed Hughes and Cresswell most often, but it is getting harder. Their latest book has numerious inconsistencies internally. I've written Dr. Cresswell in cases where he was using a rule name for two different rules. He sends me corrections that rename one rule to yet another rule name that was already in use. I've written back on that and gotten no reply.
So... I'm now following the names used by Chellas for new names, and leaving most of the others as is. However, Hughes and Cresswell's axiom E [Mp>LMp] [now axiom 5] and their axiom M (LMp>MLp) [now axiom MS] were too confusing when combined with Chella's E and M. So I've done a mass renaming of Hughes and Cresswell's names for these two axioms so that they don't conflict.
This page is http://www.cc.utah.edu/~nahaj/logic/structures/changes-1999.html
© Copyright 1999 by John Halleck, All Rights Reserved.
This page was last modified on November 30th, 2004