# Thread: simple natural deduction problems

1. ## simple natural deduction problems

Hi, I am very new to logic and would like to know the solutions for these problems

1. p -> (q -> p)

It seems that I should assume that q is true but not too sure what to do..

since this simple problem cannot be solved:

2. ((p v q) -> q)
-----------------
( p -> (p /\ q) )

I want to know the answer for this too...

Thank you very much sir.

I want to answer to be in fitch style.

Best Wishes

Sabotage

2. ## Re: simple natural deduction problems

Code:
1.   p			Assumption
2.     q		Assumption
3.     p 		1
4.   q -> p		2-3, ->I
5. p -> (q -> p)	1-4, ->I
Code:
1. (p \/ q) -> q	Assumption
2.   p			Assumption
3.   p \/ q		2, \/I
4.   q			1,3, ->E
5.   p /\ q		2,4, /\I
6. p -> (p /\ q)	2-5, ->I