Conditional logic - solution to a text book ex.

[caboose117]

Hi,

I was doing the chapter on conditional logic, and in the drill for logic chains, I got one chain right, but the I can't see why the other inference is not listed.

The question is: Being a good parent requires understanding and empathy. Those without experience cannot be empathetic.

So I did:

GP --> U
GP --> E
-E --> -GP
-U --> -GP

-EX --> -E
E --> EX

So my first answer was GP --> E --> EX but the book listed this:
-EX --> -E --> -GP

I think both are right, and one is the contrapositive of the other.

Am I wrong or did the book just overlook the other answer?

[chike_eze]

Correct.

From this:
X --> Y
-X --> -Z

We would infer:
-Y --> -X (contra of X --> Y)
-Y --> -X --> -Z