Cactus Language and Differential Logic
There's an update of my introduction to Differential Logic at this location:
This begins with a brief discussion of a formal system for propositional calculus,
the parse graphs of whose expressions are roughly what graph theorists call "cacti",
with axioms and equational inference rules that derive from C.S. Peirce's system of
"alpha graphs", the propositional part of his "existential graphs".
cc: Arisbe, CG, Cybernetics, FOM, Inquiry, SUO
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