Re: SUO: Web site on concept maps

["John F. Sowa" <sowa@bestweb.net>]

Pat,

I agree, but if people take liberties with something that
is formally defined, such as CGs, you can't expect people
to treat something that has no clear defintion to be used
the way the developer intended.

>This page uses a much more inclusive notion of 'concept map' than the 
>one Joe Novak uses, corresponding roughly to 'any graphic rendering 
>of information'. Since these terms have no formal definition I 
>suppose this isnt exactly misrepresentation, but it is sloppy and 
>potentially misleading. .

>BTW, John, is the 'one-step' Existential Graph proof shown here 
>correct? If so, why does the first consequent have only a single 
>enclosing bubble, but the second one have two?

That is a correct inference.  In algebraic notation:

   (a & b) -> c

Can be translated to: 

   ~( a & b & ~( c ) )

Add a double negation:

   ~( a & ~( ~( b & ~( c ) ) ) )

Which can be translated to:

   a -> (b -> c)

But I wouldn't consider this the best illustration of Peirce's
rules of inference.  For a better discussion of EGs, I would
recommend my commentary on Peirce's manuscript, MS 514:

   http://www.bestweb.net/~sowa/peirce/ms514.htm

John