On Feb 5, 5:43 am, "Lord Androcles, Zeroth Earl of Medway" <LordAndroc...@Januaryr2013.edu> wrote:
> > In this case, because primitives of logical expressions must be > > relations and ~e is not a relation. > > I (1) don't make the assumption that primitives of logical expressions must > be relations. I (2) assume you mean the relation "~e" to be the set of > ordered pairs (x, y) such that x ~e y. > > Since I (3) don't take logical expressions to be sets, I (4) certainly don't > take logical expressions to be relations. I (5) would prefer to say that a > logical expression may sometimes determine a set. But sometimes a > logical expression won't determine a set (e.g., the logical expression > "x ~e x" wont' determine a set.) >
not ( e(x x) ) <=> e(x,x) e not
NOT is the SET/RELATION/ATOMIC-PREDICATE
it's even PREFIX!
> Thus, I (6) say that "x ~e x" is a wff, but "x ~e x" cannot be used to > define a relation that corresponds to it. >
WFF are blind syntactic *CONSTRUCTIONS*
That they are *CONSTRUCTED* to be TRUE(wff) or NOT(wff)
does not make them predicates (ACTUALLY TRUE OR NOT) or "In-The-Language".