Categorical Propositions in
Quantificational Logic
When we introduced QL back in
Chapter 7, we looked a quantified propositions where the quantifier
ranged only over a single propositional function. That placed a severe limit on
what we could express. We could express "Everything is lovely" and there are no
unicorns" but we could not express a quantified relation among two or more
propositional functions.
We now show how to translate categorical propositions into
QL. From there, we will provid the formal semantics for QL and then its proof
theory, following the order we used for PL.