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 Author Comment/Response LogicProgramming 10/26/12 4:41pm Hi, I am new to Mathematica and am using it to program propositional logic. I'm wondering what the difference is between the If and the Implies operators. For example, both If[p,q] and Implies[p,q] return q for p=True (as a logical conditional is expected to). But when I try to obtain SatisfiabilityInstances, I get the following: - SatisfiabilityInstances[If[p, q], {p, q}] returns {{True, True}}, unless I ask it for more instances: - SatisfiabilityInstances[If[p, q], {p, q}, All] returns SatisfiabilityInstances::boolv: "If[p,q] is not Boolean valued at {False,True}." However: - SatisfiabilityInstances[Implies[p, q], {p, q}, All] returns the expected out of: {{True, True}, {False, True}, {False, False}}. Can you please explain what is causing this difference in the outputs? Thank you! URL: ,

 Subject (listing for 'Difference between If[] and Implies[]') Author Date Posted Difference between If[] and Implies[] LogicProgram... 10/26/12 4:41pm Re: Difference between If[] and Implies[] Bill Simpson 10/26/12 7:00pm
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