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Can we know anything?

  1. Oct 31, 2015 #1
    I recently engaged in Kant's philosophy and I have now a "knowledge dilemma". I understood physics to this point as the deeper understanding of nature. However, it seems to my that we are only describing nature, without fathoming the reasons why it behaves how it does. Since I was a little child, I was curious how the world around me works. But centuries of scientific engagement only describe the phenomenons we see, rather than explaining them. We have made models to describe those, but it is uncertain that those models are accurate or realistic, they just seem to work for us. Quantum theory tells us that you can not know certain things for sure, for instance at what specific point in time a radioactive nucleus will decay. This turns my whole Weltanschauung upside down, as I thought for the majority of my life that every effect has a cause. And know someone comes along, saying that there can't be a cause.
    I tried to talk about my dilemma with my teachers, however, most of them seem to be happy with the description of events.
    If you apply this to knowledge we take for granted, isn't it impossible to fathome these aswell? As a kid, I used to ask my parents a simple question, for instance: "How does a radio work?" I then continued to ask "why?" to every reply I got, until my parents weren't able to elaborate further. Doesn't that mean that every thing we know is based on something we don't know and hence becomes ambiguous? It is the same if you want so solve a system of equations with 4 variables, having only 3 equations.

    What do you think?
  2. jcsd
  3. Oct 31, 2015 #2


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    I think that this is delving into pure philosophy, and foresee this thread being closed or deleted, per the PF Rules.

  4. Oct 31, 2015 #3
    You must first understand that asking how and asking why are two very different questions.

    Science is the study of how things work.

    Metaphysics is the study of why things work the way they do.

    You can't expect the scientific method to answer why because it is not constructed to do so and for good reason. Think on that. Do you know why that is so?

    I would not get too tangled up in the discrepancies between causal and non-causal realities. You need to understand that both systems are models of observations we make in nature. Neither model is complete, but that doesn't make them worthless.

    An example would be Newtonian physics versus relativity. We all know relativity does a better description of the macro world than than Newton's equations, but it does not render Newton's work worthless. Both are tools for solving problems to their particular limits. Newton's work is perfectly fine for sending deep space probes through the solar system and are used just for that purpose. Yet, GPS satellites rely deeply on Einstein's work to complete their mission.

    Once you get a better grasp of the models we have developed in science it will be clearer to understand their strengths and weaknesses and as such where they are best applicable.

    Questions as to why the universe came to be or even why you were born lie squarely in the realm of the philosophical. It doesn't mean that philosophy is any less important than physics, just that they are two completely different disciplines and they should not be confused.

    As you go further in life you will see the treasure that ambiguity really is.
  5. Oct 31, 2015 #4


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    It would be more accurate to say that every conclusion we come to is based, either directly or indirectly, on something whose truth must be assumed instead of proven.
    That doesn't make it ambiguous. Your argument is similar to the uncontroversial proof that every dictionary must contain either circular definitions or undefined words - but that does not prevent us from using words to make unambiguous statements.

    However, none of this has anything to do with physics, which is about describing how the universe we live in works and not why we live in a universe that works that way and not some other. If you start your chain of "Why?" questions with a question about physics , the chain will eventually end when you reach the answer "Because that's how the universe we live in works".

    This issue has been extensively discussed in many threads here, and there is no need to recapitulate that discussion so this thread is closed.
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