Mid-term hiccup

• In this test paper, there is a question about two arguments with inconsistent conclusions. There are three versions of the conclusions:

1. Peter has $10. Peter does not have $10
2. Obama is married. Obama is not married.
3. John has an apple. John does not have an apple.

• In all three cases, the best answer should be "d".
  • The first three options are (a) at least one argument is unsound (b) at least one argument is invalid (c) at least one argument has a false premise.
  • Given that the conclusions are inconsistent, at least one argument is unsound.
  • There is not enough information to decide whether (b) is true, or (c) is true (or both). This depends on what the arguments are.
  • But whatever they are, if an argument is unsound, then either (b) or (c) is true, even if we do not know which it is. So if (a) is true, (b) or (c) will also be true. Thus (d) is the correct answer.
  • Arguably one might also pick (a) as the correct answer depending on how the question is interpreted.
  • In this test we shall accept both (a) and (d) as correct, though (d) is better.

How this affects you

• If you picked (d) and it was marked as a wrong answer, bring your test paper to your tutor who will update the result for you.
• If you picked (a) (or any answer which says something equivalent to "at least one argument is unsound") and it was marked as a correct answer, you do not need to do anything. Your mark will not change.
• In other cases, you do not need to do anything. Your mark will not change.

My sincere apologies.