Jacob asked in Arts & HumanitiesPhilosophy · 5 years ago

# help with this philosophy stuff!?

Update:

Im stuck on these philosophy problems and I just don't know what to do. Any help would be appreciated:

1. Prove the following valid using any of the eight inference rules.

A. (A v B) > O

B. G v ( K v J)

C. K > A

D. J > B

E. ~G / O

2. Prove the following using any of the eight inference rules of Chapters 18 and 19.

A. (A v B) > ~L

B. L v G

C. H > (A v B)

D. O > H

E. E & O / G v Z

Relevance
• Naguru
Lv 7
5 years ago

2) I can easily take you out of this serious problem. Unfortunately, I do not know your present exact location. Otherwise in no time, I can lift you through a long rope which I am having in my helicopter. Then we can both go to the Maths professor who is my close friend. He knows every thing that is now hidden in your heart.

Source(s): compiled.
• Tim
Lv 6
5 years ago

1. Show O ............. Proven Directly by 9

2. .. G v (K v J) ...... Prem. B

3. .. ~G ................. Prem. E

4. .. K v J ............... 2, 3, Disj. Elim.

5. .. K → A ........... Prem. C

6. .. J → B ............ Prem. D

7. .. A v B ............. 4, 5, 6, Con. Dil.

8. .. (A v B) → O .... Prem. A

9. .. O .................... 7, 8, MP

1. Show G v Z ......... Proven Indirectly by 13, 14

2. .. ~(G v Z) ........... Assume Neg.

3. .. ~G ^ ~Z ........... 2, DeMorgan's Law

4. .. E ^ O ............... Prem. E

5. .. O ..................... 4, Simp.

6. .. O → H ............. Prem. D

7. .. H ..................... 5, 6, MP

8. .. H → ( A v B) ..... Prem. C

9. .. A v B ................ 7, 8, MP

10.. (A v B) → ~L ..... Prem. A

11.. ~L ..................... 9, 10, MP

12.. L v G ................ Prem. B

13.. G ..................... 11, 12, Disj. Elim.

14.. ~G ................... 3, Simp.