

Logica 
Tools for Thought


1
(~q => ~p) => (p => q)
Implication Reversal Schema
2
((~q => ~p) => (p => q)) => (~p => ((~q => ~p) => (p => q)))
Implication Creation Schema
3
~p => ((~q => ~p) => (p => q))
Implication Elimination
2
1
4
(~p => ((~q => ~p) => (p => q))) => ((~p => (~q => ~p)) => (~p => (p => q)))
Implication Distribution Schema
5
(~p => (~q => ~p)) => (~p => (p => q))
Implication Elimination
4
3
6
~p => (~q => ~p)
Implication Creation Schema
7
~p => (p => q)
Implication Elimination
5
6
