• Is the following argument sound?  All students are brilliant. She is brilliant. So she is a student.
  • Expert Answers

    An illustration of the letter 'A' in a speech bubbles

    In order for an argument to be sound, it must first be valid.  So we must find out if this argument is valid.

    An argument is valid if and only if the conclusion must be true if the premises are true.  Here, we have two premises:

    • All students are brilliant.
    • ...

    Unlock
    This Answer Now

    Start your 48-hour free trial to unlock this answer and thousands more. Enjoy eNotes ad-free and cancel anytime.

    Start your 48-Hour Free Trial

    In order for an argument to be sound, it must first be valid.  So we must find out if this argument is valid.

    An argument is valid if and only if the conclusion must be true if the premises are true.  Here, we have two premises:

    • All students are brilliant.
    • She is brilliant.

    We have one conclusion:

    • She is a student.

    So we ask: can she be something other than a student and still be brilliant?

    The answer is yes -- nothing in the two premises says that only students can be brilliant.  All students are brilliant, but that does not mean that other people cannot be brilliant.

    Therefore, this argument is not valid.  If an argument is not valid, it cannot be sound either.

    Approved by eNotes Editorial Team