Identify what you can properly conclude from the given premises:P: A → MP: not X → JP: X → not MC: ?

ehay July 14, 2019

Clarification

So basically (1) make contrapositives of the original premises, (2) form a chain argument from the original premises & contrapositives (3) Derive the conclusion based on chain argument rules [1. Every statement is a conditional, 2. The antecedent of the first premise = antecedent of the conclusion, 3. The consequent of each premise = the antecedent of the following premise, 4. The consequent of the last premise = consequent of the conclusion]. (4) make a contrapositive of the conclusion. ... So after step 1, you make the chain based on chain argument rules looking for conditionals (from original & contrapositives premises) in which the consequent matches the antecedent of the other... come to conclusion based on the antecedent and consequent of the chain, and then make a contrapositive of the conclusion. Why exactly is the contrapositive of the conclusion the only conclusion we can properly conclude if there is a non-contrapositive conclusion derived from chain argument rules?

Create a free account to read and take part in forum discussions.

Already have an account? log in

Ravi July 30, 2019

@ehay,

The chain we get is

/J - >X - >/M - >/A

The question isn't saying that the only conclusion we can get is
/J - >/A; rather, what the question is asking us is which of the
following can be concluded?

The only answer choice that can be concluded is (C), which states
/J - >/A. All of the others can't be concluded, and (E) is patently
false since we do have a valid conclusion.

Does that make sense? Let us know if you have any other questions!