4.0 Teaching of Applied Logic. There are two major problems that have to be solved if we want to make logic accessable and useful to computer scientists. First, as Dijkstra has claimed for many years, logicians learn, teach and explain logic in order to facilitate the study of logic itself. Secondly, most logic books skip over the overall structure of logic and assume equality either as a god-given additional axiom or as the consequence of implication in both directions. Both points of view slow down comprehension for a typical freshman student to whom implication is foregn and an understanding of equality is fuzzy.
Equational logic is a delightful exception in the handling of equality.
One is based on model theory with truth tables encapsulating all models of a wff. The other is based on proof theory where purely syntactic derivations using appropriately chosen axioms and inference rules surprisingly and amazingly give the same results as truth tables and interpretations. 5.0 Acknowledgements The author is grateful to a number of colleagues for comments, suggestions, ideas and laboratory materials, especially to Mikhail Auguston, Hue McCoy, Ann Gates, Ming Sheu, Mannish Mamnani and Jay Turley. Many thanks to our students and teaching assistants who helped to make each subsequent version of the course a little better than its predecessor. Many thanks to the National Science Foundation for two research grants without which our course would not have gotten off the ground.