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May 31, 2006 02:58PM
Hi Guys

I'd like to know if we'd be penalized if we used the syntax style used in The Languages of Logic by Guttenplan?

avatar Re: Syntax
May 31, 2006 05:26PM
I'm doing my deductions using a hybrid of the Gutenplan and LPL methods.

I'm numbering every line and putting the truth reliance numbers in as well but I'm using LPL's way of doing the disjuction elimination. It's easier to follow than Guttenplan. I'm not using the Fitch bars, I find them annoying. I can follow the different proof/subproofs without having to draw lines all the time.

Oh, I'm also just using I and E instead of Intro and Elim.

e.g. Gutenplan format:

1         (1) P v Q          Premise
2         (2) ¬P             Premise
3         (3) P              Assumption
4         (4) ¬Q             Assumption
2,3       (5) P & ¬P         2,3 &I
2,3       (6) ¬¬Q            4,5 ¬I
2,3       (7) Q              6 ¬E
8         (8) Q              Assumption
1,2       (9) Q              1,3,7,8,8 vE

LPL of the above:
| 1. P v Q        
| 2. ¬P          
| | 3. P     
| | 4. ¬Q            
| |-
| | 5. _|_                   _|_ Intro: 2,3
| 6. ¬¬Q                     ¬ Intro: 4,5
| 7. Q                       ¬ Elim: 6
| | 8. Q            
| |-
| | 9. Q                     Reiter
| 10. Q                      v Elim: 1,3-7,8-9

The way I'm doing it:
1         (1) P v Q          Premise
2         (2) ¬P             Premise
3         (3) P              Assumption
4         (4) ¬Q             Assumption
2,3       (5) P /\ ¬P        /\I 2,3
2,3       (6) ¬¬Q            ¬I 4,5
2,3       (7) Q              ¬E 6
8         (8) Q              Assumption
1,2       (9) Q              vE 1,3-7,8-8
Re: Syntax
May 31, 2006 08:36PM
Hi Rob

Thanks for the tips. I allready handed my assignment in :/

Tried with the new scheme, but I think it's reception will be luke warm heheh.

I do hope that the moderators will get back to us on this subject.

Personally I'd like to use the exact syntax as in Guttenplan, you tend to worry less about layout ( score keeping fixes this ) and more about getting the logic right.

Re: Syntax
June 07, 2006 04:24PM
You are required to use the fitch deductive system given in Chapter 6 onwards in your prescribed book not Guttenplan's deductive system.The useful part of Guttenplan deductive system you are to follow are his ten rules.They do apply to our formal proofs.

avatar Re: Syntax
June 07, 2006 05:43PM
Oh Well

Looks like I'm going to lose a few marks for style - I didn't put in Fitch bars.

If this is how we're supposed to do it, does anybody know how to put in the Fitch bars on Word without it being a exercise in itself? The pipes and dashes I used above look ugly compared to the textbook and they were a bitch to type in. (That's the main issue I have with them - not computer-friendly)
Re: Syntax
June 20, 2006 06:30PM
Yip, It was a bit of a mission in word initially,
But I ended up cutting and pasting line objects and it did not take too long in the end.

Re: Syntax
August 08, 2006 11:20AM
i also did it the hard way, though thinking about it now it would be really easy to set your tabs to prefix with _, then when done find&replace with |
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