(urth) I, even I, would celebrate, in rhymes inept the great...

[Jeffery Wilson clueland.com]

On 10/15/2014 1:28 PM, Norwood, Frederick Hudson wrote:
> I notice that none of the "we can never know anything absolutely"
> team on this thread has accepted my challenge to explain how A can be
> true, and A implies B can be true, and yet B can be false.

That is known as modus ponens (the method that affirms), but that's 
short for modus ponendo ponens (the method that affirms by affirming), 
and as the longer Latin name implies, its truth is complicated by an 
infinite regress, as dramatized by another famed fantasy author:

http://en.wikipedia.org/wiki/What_the_Tortoise_Said_to_Achilles

If you consider a true statement about abstracted symbols to be an 
absolute truth, why not save steps and just say "A is A"? That remains 
valid regardless of the values of A or B or the validity of modus ponens.

-- 
Jeff Wilson - < jwilson at clueland.com >
A&M Texarkana Computational Intelligence Lab
< http://www.tamut.edu/cil >