This installment of the notes contains considerably more material than just "semantics". Unfortunately, it is somewhat obsolete. These notes define a logic as a language together with a semantics. In the current lectures the language is always defined by a grammar and the concept of a grammar is part of the defintion of a logic --- a logic is a grammar for a language and a specification of a semantics. There is one case in the semantic specification for each production in the grammar. Grammars are not explicitly included in the definition in the notes.
These notes also contain a lengthy discussion of particular inference algorithms which can be applied over a wide variety of logics. In the current lectures these inference algorithms are only mentioned briefly.
The main concepts contained in these notes are the general concepts of soundness and completeness for inference rules. Although technically very simple, these concepts seem to be enormously difficult for operationally-minded computer science students.
David McAllester, February, 1995