Propositional Logic Functions
Read sections 2.2 through 2.4 (p. 51-75) to learn how to identify and apply propositional (or sentential) logic functions. Using these symbols, you should be able to turn statements into symbolic formulas to more clearly see the logical connections taking place, and determine when the conclusions are valid. It can look confusing at first, but moving slowly through these units will allow you to make valid logical proofs.
Complete exercises 8, 9, 10, and 11, and check your answers against the answer keys on pages 211-215.
Note that the symbols used in some places can be slightly different from ones used elsewhere. This is because there is not one standard set of symbols used for sentential logic, but a few. This table shows you the differences and helps translate between them.
In the resources in this course, the symbols for disjunction and negation are the same in both systems, but the symbols for conjunction, conditional, and biconditional are different.
Name | Meaning | Symbol 1 | Symbol 2 |
Conjunction | and | & | • |
Disjunction | or | v | v |
Negation | not | ~ | ~ |
Conditional | if/then | → | ⊃ |
Biconditional | if and only if | ↔ | ≡ |