Hint for Section 1.2 Question 5

5. The statement "I say what I mean" can be rewritten as "If I mean it, then I say it." The statement "I mean what I say" can be rewritten as " If I say it, then I mean it." Now let p be ``I say it'' and let q be ``I mean it'', and write the two statements in symbolic form.

The two statements are q implies.jpg (563 bytes) p  and  p implies.jpg (563 bytes) q.  Use a truth table to show that these statements are not logically equivalent. There are two statement variables so the truth table will have 4 rows.

p q   q implies.jpg (563 bytes) p p implies.jpg (563 bytes) q
T T      
T F      
F T      
F F      

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