 Sentential Logic | |
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DitzyDoo
Newbie Usergroup: Members Joined: Feb 21, 2012 Total Topics: 3 Total Posts: 9 |
 #1
Subject: Sentential Logic rules available. MP, MT, DS, Simp, Conj, HS, Add, CD, DM, DN, Comm, Assoc, Dist, Contra, Impl, Exp, Taut, Equiv. Premise 1: R -> (~A & T) Premise 2: B-> ~S Premise 3: R v S Conclusion: A ->B |
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Willemien
Intermittently sane Usergroup: Sponsors Joined: Apr 05, 2011 Location: London (UK) Total Topics: 36 Total Posts: 572 |
#2
DitzyDoo wrote: rules available. MP, MT, DS, Simp, Conj, HS, Add, CD, DM, DN, Comm, Assoc, Dist, Contra, Impl, Exp, Taut, Equiv. Premise 1: R -> (~A & T) Premise 2: B-> ~S Premise 3: R v S Conclusion: A ->B come on, what were your own ideas about it. and you have a strange muddle of rules What is the difference between Comj and Add? And between MT and Contra? And that rule Taut, can you just add "Sum(premisses ) -> Conclusion" as tautology? which book are you using anyway? (So i can know if you want a lemmon style or a Fitch style proof) |
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DitzyDoo
Newbie Usergroup: Members Joined: Feb 21, 2012 Total Topics: 3 Total Posts: 9 |
#3
Using a book by Alan Hausman conjunction (conj) is 1. p 2. q / p & q addition (add) 1.p / p v r (r is any wff) MT is modus Tollens 1. p -> q 2. ~q / ~p Contra p -> q <-> ~q -> ~p Tautology (Taut) p <-> p & p p <-> p v p |
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Willemien
Intermittently sane Usergroup: Sponsors Joined: Apr 05, 2011 Location: London (UK) Total Topics: 36 Total Posts: 572 |
#4
Did not know that book.  (and had a look at amazon , it has a Fitch style structure (or more a Kalish style)I doubt if you are able to do this with only the rules given. I think you will need the rule AP |
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DitzyDoo
Newbie Usergroup: Members Joined: Feb 21, 2012 Total Topics: 3 Total Posts: 9 |
#5
I assure you that it should be able to be done without using Assumed Premise. The section said it may take quite a few line. Working on it. I at least got to a premise which states R -> (A -> B) (A->B) is our conclusion So if there were a way to get R by itself only way to do that by by simplification) other two premises are B v ~S R v S Is there some way of getting R by itself without AP using these premises? |
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DitzyDoo
Newbie Usergroup: Members Joined: Feb 21, 2012 Total Topics: 3 Total Posts: 9 |
#6
Thanks! I was able to figure it out. |
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