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Some modest questions.

  1. Mar 1, 2007 #1
    In the book "Surely You're Joking, Mr. Feynman", by Richard Feynman, on page 70 in the section entitled "A Map of the Cat" is the following (emphasis his):

    What do you make of this statement? Surely no one here thinks that Professor Feynman was unaware of the experimental evidence in support of the theory. Why almost real, not really real?

    Later in the same paragraph he says:

    Can you explain the analogy to me so I can understand it better?

    Please do not accuse me of taking him out of context. I have given you the name of the book and the page number. If you feel that there is important context that I have left out, please add it to this thread.

    The book in question is not a scientific text, it's not even a popularization of scientific ideas. It's a kind of autobiography. Did he in his scientific writings say that electrons were not a theory?

    In his book QED, which is a popularization of scientific ideas he writes on page 4:

    What do you make of it?
    Last edited: Mar 1, 2007
  2. jcsd
  3. Mar 1, 2007 #2
    I have not read the book but from a different discussion I think I know what you are getting at. I am interested in your query. I believe the fundamental question has merit both philosophically and scientifically.

    A mentor has stated in a different thread that solipsism is impossible to disprove. If so then all we can absolutely rely on is our own perceptions. They may be inaccurate, they may be skewed, but they are the only available way for our mind to communicate with anything outside of itself. In spite of the possible inaccuracy of our perceptions, we can still form theories to explain our observations of what we perceive as happening in the world external to our own mind.

    The use of measuring instruments certainly provides an extension to our senses but in final analysis we do not perceive what they do, we only perceive their output. Is it more accurate to say that "North is this way" or to say that "the compass points this way"? The former is a conclusion whereas the latter is a perception. We can directly perceive the output of a measuring device (the compass) and know that this is what we saw. We cannot be sure that what we saw was completely accurate, but once again what we see is all we have: the compass points this way. (And "see" is the correct term here since we cannot smell, taste, listen to or touch the needle under the glass.)

    The conclusion that "North is this way" is a deduction. It may be false because the compass' pivot may be rusty, the needle may be demagnetized, because the device points to magnetic North when we may want true North (a common mistake). Other factors I am not thinking about can possibly make our conclusion incorrect. So a conclusion that "North is this way" relies on trust in the instrument we use and trust in theories regarding relative stability of magnetic earth and so on. I think this is an important consideration (again, both philosophically and scientifically).

    I don't have the context of the book but it sounds like he means that the theory has proven itself repeatedly and is eminently useable, yet it remains a theory. Just like the compass theory. It is falsifiable.

    No context needed here. When I look at a solid, I only see the surface with my own eyes. I assume that there is something inside, that is, I formulate a hypothesis. To confirm my hypothesis, I break the brick and look at the result of my experiment. Unfortunately, I still only see the outside of the pieces, a surface once again. There may be a new surface where the brick was split, but I still do not see the "inside" I was looking for. My senses do not allow me to see through the brick material so no matter what I do, all I ever see is more and more surface.

    I easily resolve this limitation of my senses by formulating a "theory of the inside" which stipulates that whenever I break a solid, its "inside" property causes a new surface to be created. I can never see the inside of the brick but my theory that it is there is proven time and time again: all experiments confirm the inside property.

    Next step: find a way to peer inside solid matter. I cannot do this myself but I can devise instruments that appear to be able to do this using ultrasounds, X-Rays, etc. Then, like the compass, these instruments become an intricate part of other theories.
  4. Mar 1, 2007 #3


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    Feynman has also said "Shut Up And Calculate". How come you don't heed that one?

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