Proof by induction. Monday, Jan. 15 University Holiday DAY 6. Wednesday, Jan. 17 Truth functionality. The method of truth tables. Jan. 19 Overview of the truth table method, looking at it as a special case of truth-based semantics.
Truth tables provide an algorithm for determining validity.
But because of a combinatorial explosion in constructing all the rows of the table, this algorithm is infeasible for formulas containing more than a few different sentence letters. Contrasting semantic and proof-theoretic approaches. Consistency as a notion that could be defined either way. Rules for derivations. Some examples involving only conditional formulas.