On the Model Theory of Knowledge - An essay by John McCarthy on the use of model theory, with a bias towards knowledge representation. Strong on Kripke models.
Sellars-Harman Correspondence - Correspondence between Wilfrid Sellars and Gilbert Harman on truth. Illuminating discussion on the issue of whether a Tarskian semantics provides an adequate basis for a correspondence theory of truth.
Singular Propositions - Singular propositions (also called `Russellian propositions') are propositions that are about a particular object or individual in virtue of having the object or individual as a constituent of the proposition. From the Stanford Encyclopedia, by G. W. Fitch.
The Theory of Abstract Objects - Web resource provided by Edward Zalta, centering upon his `Principia Metaphysica', a general calculus for the expression of theories of abstract objects. Includes a tutorial section.