FOM: geometrical reasoning

[Stephen G Simpson]

Michael Thayer writes:
 > For what if there were something provable diagrammatically, which
 > was not provable in the system?

This scenario suggested by Thayer can't happen, because the system
under discussion (Harvey's system in 1 Feb 1999 04:52:48) is complete.
Also, it appears that Thayer has overlooked Seligman's remark:
"Typically, diagrammatic systems of representation are expressively
weaker than predicate logic, ...."

-- Steve