This question comes from a GD thread discussing the Pope Benedict XVI’s recent pronouncement on health care. But the logic question is not really related to that topic.
Here are four quotes from the GD thread:
Quote 2 (me responding to Bricker)
Quote 3 (John Mace responding to me)
Quote 4 (Bricker responding to me)
p = “abortion should be / is illegal”
q = “UHC should be government policy”
In (quote 1) in this thread, Bricker is saying
If p, then q. (if abortion is illegal, I agree that UHC should be government policy)
Bricker’s link (quote 4) says:
“If a statement is true, the contrapositive is also logically true.” and defines
“statment: if p then q”
“contrapositive: if not q then not p”
The contrapositive “If not q then not p” would be
“If UHC is not government policy, then abortion should be legal.”
which is what I said in Quote 2 above. What I said in Quote 2 was the contrapositive, not the inverse, and Bricker is mistaken in Quote 4 in calling it the inverse.
My statement in quote 2 (the contrapositive of quote 1) is logically derived from Bricker’s statement in quote 1.
Where am I wrong? I am assuming, based on the responses from John Mace and Bricker, that I am making some basic mistake in logic?!?!