Presented at the ACM’s 24th Technical Symposium on Computer Science Education, 1993 and later published in the SIGCSE Bulletin, 25(1), March 1993, pp. 232–236.
Abstract
Truth tables are a basic tool for teaching propositional logic. However, when students are unfamiliar with logic or come from educationally disadvantaged backgrounds, definitions of logical connectives based on truth tables are unintuitive and difficult to remember. This is especially the case with the truth table for material implication.
Possible Models Diagrams are a visual representation of propositional expressions and hence offer an alternative to truth tables. Like truth tables, Possible Models Diagrams can be used to define basic logical connectives and to classify well-formed-formulae as tautological, contingent or inconsistent. In addition, they show greater expressibility than truth tables in that they can be used to show whether or not a sequent is provable. Furthermore, they are simpler to learn and to remember because of their visual appeal.