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8.6: Fallacious Appeal to Authority

  • Page ID
    22004
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    You know that the moon is a big, hard rock, don't you? It looks that way. But wait! How do you know? How do you know it's not made out of soft plastic? You've never been to the moon. You could be wrong, couldn't you?

    Don't let that last question intimidate you. You don't have to go to the moon to know about it. You know the moon is a big, hard rock because you have probably read that fact in a science book or heard it from a science teacher. Science teachers can speak with authority on this matter. If you believe that the moon is a big rock for a reason like this, then you know it. Much of what you know you have learned this way. You don't find out for yourself; you believe what authorities say, at least when you can be reasonably sure they are in agreement with each other. You are right to do so. It is not firsthand knowledge, but it is still knowledge.

    Suppose you came to believe that the moon is a rock only on the basis of what your sister told you. Then you wouldn't know the truth about the moon, assuming that she is no authority. You would believe the truth about the moon, but you wouldn't know the truth. To have knowledge you need more than true belief. To know something, you have to have solid justification for it. Knowledge is justified true belief; your knowledge is your true beliefs that you could back up by good reasons. The reasons are crucial; without them you just have opinion, not knowledge.

    If you were to learn that some person's supposed knowledge turned out not to be true, then you would say the person never really knew it after all. For example, in Medieval times many people thought they knew the Earth to be flat, but they were mistaken and didn't really know it. They did have a justification for believing what they believed: they could climb a hill, look out, and see that the world appeared to be flat. That was good evidence for the time. Yet their belief was not knowledge, even though it was reasonable for them to hold the belief. In other words, they had a good reason to believe something false, but because it was false it was not knowledge.

    Exercise \(\PageIndex{1}\)

    Without having a justification, a person's claim to have knowledge is unsuccessful, but with the justification the person’s claim

    a. will never be mistaken and will really know.
    b. might be mistaken.
    c. will always be mistaken, and thus the person will not know.

    Answer

    Answer (b). With the justification, the claim could still fail to be knowledge; it must also be true

    If you answered that concept check correctly, then you’ll have no problem with this one.

    Exercise \(\PageIndex{1}\)

    Explain the error in the following sentence, then rewrite it to make the point correctly:

    In Medieval times, people knew that the world is flat, but we now know that it's not flat.

    Answer

    It is a mistake to say that the people knew the world is flat. People never knew this because people cannot know something that is false. Here is a way to make the point correctly: In Medieval times, people believed they knew that the world is flat, but we now know that the world is not.


    This page titled 8.6: Fallacious Appeal to Authority is shared under a CC BY-NC-SA license and was authored, remixed, and/or curated by Bradley H. Dowden.

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