Solutions to Homework #9, Problems 23-29

Now, since we are assuming B, and because we know B ( C, C follows, by modus ponens. Since we were able to prove C by assuming A ( B, we know that A ( B imply C. 3. Weakening the Consequent: From A ( B infer A ( (B ( C) In addition to our premise A ( B, let’s suppose A. Now, given these statements, B follow by modus ponens. ................
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