Uncontrolled vocabularies
"I try my best to make *all* my posts nice, even when I feel upset" -- Philippe Maquet
Uncontrolled vocabularies
"I try my best to make *all* my posts nice, even when I feel upset" -- Philippe Maquet
Originally posted by Mapraputa Is:
It was recommended to Pakka Desi and me to form "logic study group". Dunno about Pakka, but I am actually interested. Not sure if there are many people interested around this forum, but let's try...
In particular, I was surprised by the following comment, that shows how what I considered pure abstraction can find some practical applications.
"What does it mean to say Bush is a Democrat is false not not necessarily false? If it's false, it's false. Eventually, this all led me to work on possible worlds, naming, and necessity, Well, to get more practical, here is The list of logical fallacies that I found useful.
Originally posted by herb slocomb:
Regarding "necessarily" true or false; from my memory I had thought that something was necessarily true or false based on given assumptions or statements. For example, Herb is a great programmer and all great programmers know Java. Therefore, it is necessarily true that Herb knows Java. (maybe a bad example...)
Distinction between kinds of truth. Necessary truth is a feature of any statement that it would be contradictory to deny. (Contradictions themselves are necessarily false.) Contingent truths (or falsehoods) happen to be true (or false), but might have been otherwise. Thus, for example:
"Squares have four sides." is necessary.
"Stop signs are hexagonal." is contingent.
"Pentagons are round." is contradictory.
Originally posted by Jason Menard:
Given your example: "Herb is a great programmer and all great programmers know Java. Therefore, it is necessarily true that Herb knows Java." Wouldn't that be a contingent truth?
Uncontrolled vocabularies
"I try my best to make *all* my posts nice, even when I feel upset" -- Philippe Maquet
"I'm not back." - Bill Harding, Twister
Originally posted by Jim Yingst:
I remember being perplexed that any arbitrarily complex logical statement can be express with only "NOT", AND, and OR functions
Or, for bonus points, using only NAND gates. Well, it's trivial to just replace AND/OR/NOT with equivalent NAND combinations - extra points are only merited if you bother to minimize the number of NANDs used.
[ January 29, 2003: Message edited by: Jim Yingst ]
"Thanks to Indian media who has over the period of time swiped out intellectual taste from mass Indian population." - Chetan Parekh