Solutions to Homework #9, Problems 23-29

What I’ll want to show is that C ( D follows from our premises no matter which side of the disjunction A ( B is true. Let’s take A first. Assume A. If A and A ( C, C follows by modus ponens. Since we know that C true, then can assert a disjunction C ( D because it doesn’t matter whether D is true or not, by the definition of (. Now assume B. ................
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