Summary
	Whew! That was a loooooooong lecture.  What did we learn? ¡ Enumeration: DPLL rules are similar to CSP heuristics. ¡ Resolution is proof by refutation, used in PL. ¡ Other forms of reasoning: Modus Ponens which requires Horn form. ¡ FOL uses unification to find solutions, requires Skolem constants and functions. ¡ Forward (undirected) and Backward (directed) chaining patterns to apply an inference mechanism.