From: peirce-l-requ...@list.iupui.edu on
behalf of Jon Alan Schmidt
Date: Thursday, March 7, 2024 at 7:42 PM
To: Peirce-L
Subject: Re: [PEIRCE-L] Problems in mixing quantifiers with modal logic (was
Delta Existential Graphs
John, List:
It looks like you sent the message quoted below only to me
John, List:
It looks like you sent the message quoted below only to me, but I assume
that you intended it for the entire List, so I am replying accordingly.
JFS: In the copy of your note, included below, please note that the five
EGs are *BETA *graphs. The lines of identity refer to things that P
John, List:
JFS: In his letter on Delta graphs, Peirce was breaking new ground. He was
proposing a totally new foundation for modal logic, based on metalanguage.
There is no "letter on Delta graphs." Peirce wrote only *one sentence* that
mentions them in a letter to Risteen (R L376, 1909 Dec 6),
M
To: John F Sowa
Cc: Jon Alan Schmidt , Peirce-L
Subject: Re: [PEIRCE-L] Problems in mixing quantifiers with modal logic (was
Delta Existential Graphs
John,
I have been following this exchange between you and Jon Alan with considerable
interest. Thank you both for discussing these most inter
John,
I have been following this exchange between you and Jon Alan with
considerable interest. Thank you both for discussing these most
interesting -- and I think, important matters relating to modals, Delta
graphs, etc. -- in the generally collegial manner in which you have been
proceeding.
You
Jon,
The first point to emphasize is that Peirce's primary goal in the last decade
of his life was to provide a proof of pragmatism. That would require a system
of logic that could express and analyze rather sophisticated texts about
science. The metalanguage of the IKL logic in 2006 is very
John, List:
JFS: One reason why I did not respond in detail to your previous note
(copied below) is that your citations to the writings by Dunn and Goble
only apply to PROPOSITIONAL modal logic (no quantifiers).
I have acknowledged this all along--my candidate for Delta EGs is an
extension of *A
Jon,
One reason why I did not respond in detail to your previous note (copied
below) is that your citations to the writings by Dunn and Goble only apply to
PROPOSITIONAL modal logic (no quantifiers). Every version of modal logic that
Peirce developed included existential graphs as the base lo
