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The impossibility of certainty

  1. Jan 26, 2005 #1
    The argument is, if you believe anything, you must have come to your belief through some process. If the process had an undiscoverable flaw in it, it would be invalid. Moreover, it is not possible to tell whether any process has a flaw which is undiscoverable. So there is no absolute way to tell whether any reasoning is valid or invalid.

    This may seem a little strange, but think of it as making mistakes. No matter how many times you check your work and how sure you may seem, there is no way to know for certain that you didn't make a mistake somewhere.

    Quantum uncertainty is a possible mechanism for undiscoverable flaws. Every particle has some nonzero chance of being found almost anywhere. So it is possible, albeit unlikely, that the action of any system could be drastically different from the way you expect it to go. Any reasoning carried out must be done by some system, such as your brain or a computer. There is a tiny chance that your brain or the computer will act drastically different from how you would expect it to--for example, in such a way as to arrive at the same wrong answer, completely randomly, every single time.

    This possibility may seem negligible, but consider that your judgment that it is negligible is simply the result of a process in your brain, and subject to the same quantum effects as anything else. So there is a chance that your judgment that it is negligible is completely wrong, and it actually is quite common for a system to arrive at the same wrong answer through random quantum effects every time. So long as the probability-judging processes are susceptible to any error--no matter how improbable such error seems--there is no way to know how likely or unlikely error in all your thoughts is.
  2. jcsd
  3. Jan 26, 2005 #2
    I've always wondered why people even believe in certainty. I'm not saying that you should certainly hold to uncertainty either, but why worry about it? It seems like such a strange distinction in the first place.
  4. Jan 26, 2005 #3
    Certianty to me just seems more solid. If everything turned out certian then there is no paradox. If everything turns out uncertian then something about that statement just won't ever have a complete answer.
  5. Jan 26, 2005 #4
    The universe is very versatile. Anything can be going on in it that we had never thought of. In fact out perception of the world is very narrow. For us, tomorrow is a day to go to school and submit the maths assignment, but for the universe, tomorrow is just a period of time which will be called 'tomorrow' by the stupid human beings on the uncharted planet earth. A lot is going on in there. The reality is different.
  6. Jan 27, 2005 #5
    Vintner, this uncertainty extends to things like 2+2=4.
  7. Jan 27, 2005 #6
    People believe in certainty because they want to. I've tried to explain the entire process of uncertainty to people that I know, and yet, they don't want to grasp it. Most of society need a firm grasp on something they can call the truth, and thus, even if they realize it's fake, they'll still be predisposed to just that.

    Err, Bart, are you sure it extends to 2+2=4? If it did, we'd have to have this huge "what is time" debate... wouldn't we? I thought mathematical equations wern't subject to uncertainty, because it's just a concept that we've discovered. Tomorrow will always be tomorrow, because we define it... right?
    Last edited: Jan 27, 2005
  8. Jan 27, 2005 #7
    We cannot know the answer, but an answer exists!
    Last edited by a moderator: Jan 27, 2005
  9. Jan 27, 2005 #8
    Yes, the reasoning in my first post of this thread applies to 2+2=4 just as it applies to every other idea. There's no reason to make any exception.
  10. Jan 28, 2005 #9
    Now that's bad news: if we can't trust mathematics, what can we trust?
  11. Jan 28, 2005 #10
    Probability can be explained with a certianty model. I'm sure it is very possible.
  12. Feb 1, 2005 #11
    If nothing for certain is correct, then this statement is also not for certain and so some things or everything are for certain, even though logically nothing is for certain.


    'Nothing is for certain' is a circular argument and a statement is needed which properly defines the argument we are trying to represent.

    The statement is as follows.

    'Nothing can be completely proved.'

    I remember discussing this with somone about a year ago. This is the conclusion we came up with.

  13. Feb 1, 2005 #12
    What I meant is the reason why probability exist can evenutally be explained by making a certianty model. Of course there would be no probability when that happens.
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