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To predict is to explain?

  1. Aug 26, 2004 #1
    The goodness of a scientific theory,as Relativity or QM, is related to its prediction's power.

    But when could we assert that we explain anything? Only in basis to prediction (or "retrodiction") ?
  2. jcsd
  3. Aug 26, 2004 #2
    Words only have demonstrable meaning according to their function in a given context.

    Is that a good enough explanation for you? :0)
  4. Aug 26, 2004 #3
    No. You ever talk about context. Well. Choose one.
  5. Aug 26, 2004 #4
    When is an explanation not an explanation? When no one can understand it, not even the author, or whenever someone does not see it as an explanation.

    "Goodness" is a value judgment, not a scientific assessment. Exactly what is the goodness of being able to predict, for example, that you cannot predict something? It has no demonstrable inherent "goodness" and some might say it is utterly useless. It just depends upon who is making the value judgment.
  6. Aug 27, 2004 #5
    Predicting that you cannot predict something can be very valuable, as it narrows down the field of variables you explore in a system. I see no reason to pick on the original posters use of the word "goodness." Maybe value or scientific value might have avoided the problem, but surely everyone understood what he meant.

    Physics is judged by it's ability to predict past, present and future variables. To answer the original question, I do not see physics as explaining anything, nor do I think it should. I'm not convinced things around us can even be "explained" the way people use the word, by science or philosophy.
  7. Aug 27, 2004 #6
    It seems that that's the case with Gödel's theorem...
    Yes. Strictly, "goodness" is a value judgement. Strictly, explanation isn't a scientific term. Strictly, we only could talk in a mathematical language. Alternatively, we would must previously agree about the significance of each term that we use as prediction, explanation, goodness...
  8. Aug 27, 2004 #7
    I find your answer very interesting. It is clear that a scientific theory must be capable of prediction. But why must "explanation" be out of Science?
  9. Aug 27, 2004 #8
    My answer would be that I define science as that knowledge that comes from the scientific method. I do not believe the scientific method can always appropriately distinguish between various explanations. What's more, explanations can be invalidated by new discoveries, whereas the experiments that created them sometimes aren't.

    The "explanation" that was produced by newtonian mechanics is clearly disproven in light of 20th century physics. An yet I use newtonian mechanics all the time. It works great within the realm of the experiments done to prove it an acceptable theory. I could sit around worrying about whether the explanation derived from a new theory is good or bad, but who cares? The explanation is temporary. It's predictive power is not.

    It is also possible to insert extraneous information into an explanation that does not affect the nature of its predictions. Scientists respond to this by employing Occam's razor; but Occam's razor is not science, it is a philosophical tool. How can one justify using a tool to determine what is "science" that is not based on the scientific method when distinguishing between two explanations that both rely on predictions found by the scientific method?

    I don't mean to suggest that creating non-mathematical interpretations of theories is useless. I think it is a useful tool for conducting science. Of course, so is a computer, but that doesen't mean a computer is science, or that science is responsible for the quality of computers manufactured.
  10. Aug 27, 2004 #9
    I prefer to define science as the pursuit of knowledge of the natural universe, using various empirical and logical methods (the scientific method being only one, yet most popularly known, variety). The "bits" of knowledge are facts, and the facts are inductively analyzed to form a scientific theory. Scientific theories are proposed explanations of the facts and are inherently tentative and fallible by virtue of the induction process that was involved in their creation.

    As time passes, as more research opens up new possibilities, as new brains step up to the plate, scientific theories should become more and more aligned with the "true" underlying explanation of the natural universe (aka Theory of Everything). This process has been observed when comparing Newton's Law of Gravity with General Relativity. Newton's Law of Gravity is very accurate and useful...to a point. General Relativity is a "sharper" theory that seems to be more closely aligned with the "true" explanation. Some other theory, Theory X, may turn out to be "sharper" than General Relativity, thereby unseating Einstein.

    The progress may be asymptotic, in the sense that we may never actually reach the "true" explanation, but the pursuit itself is really where much of the aesthetic pleasure, excitement, and "goodness" of science is located IMO.
  11. Aug 30, 2004 #10
    That is an interesting difference. :approve:
    If I understand your position, the scientific knowledge would be linked directly to the prediction's power of scientific theories, whereas explanation could imply other factors, as you show with the reference to the Occam's razor.
    Prediction's power would be strictly scientific
    Explanation would be also related with the personal and historical "Weltanschauung". Are you in agreement?
  12. Aug 30, 2004 #11
    I agree completely with your asymptotic image of progress. :smile:
    I find very interesting your reference to the relationship between "the pursuit" and the "aesthetic pleasure". From my viewpoint, as I posed in other thread, the relationship of this aesthetic pleasure with scientific activity would arise from the fitness of theories to Nature in a form of Aristotle's mimesis (Poetics).
  13. Sep 4, 2004 #12
    Prediction, description, explanation and understanding. Are all they scientific terms?
  14. Oct 4, 2004 #13
    Knowledge and QM

    QM is a good theory because of it is highly predictive. That is Science. But there are diverse "interpretations" of QM. Are these interpretations scientific or philosophical approachs? :rolleyes:
  15. Oct 5, 2004 #14


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    Well some good scientists are obsessed with them. I don't think there's a big nanny who says what science is or is not. Science is what the people who do it say it is. And if there is disagreement on what they say, so be it.
  16. Oct 6, 2004 #15
    That is a circular argument. Scientists would be also the people that do Science. Philosophy and Science are different things and this difference would apply also to interpretations of quantum mechanics.
  17. Oct 6, 2004 #16


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    So, how can science be defined, in terms that have high relevance to the real world of what scientists do?
    Last edited: Oct 6, 2004
  18. Oct 6, 2004 #17


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    No it isn't circular, because science is historical (or if you prefer, dialectical), so the definitions of one generation react with the self definition of the next to update the definition of science. If you had asked Newton what he was doing you would have gotten a very different answer than if you posed the same question to Maxwell, Einstein, or Witten.
  19. Oct 7, 2004 #18
    Probably, Newton and Maxwell would say that they were doing Philosophy of Nature
    Yes, Science and definition of Science are made in a historical context. But if Science is that scientists do and scientists do Science, the expression seems to be circular.
    There are problems with definitions when Science is very entangled with Philosophy, and such is the case in QM interpretations. When a scientist express his worldview he is not doing science, although his worldview result from his scientific activity.
  20. Oct 7, 2004 #19
    I don't know now any definition absolutely valuable.
    Science would be by one hand a work: the use of the scientific method to explore the Nature, being the scientific method one based in experimentation, observation, logic deduction and induction. A key factor in this method would be the communication in a common language, being mathematics the best form of expression.
    On the other hand, Science would be the whole of knowledge obtained by the scientific method. This knowledge would be the substrate of predictive theories.
  21. Oct 7, 2004 #20


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    IOW, wherever we can determine that these elements have been used (consciously? unknowingly??*), we can call the activity 'science'?
    So without maths it's just not science? Or the use of math is a heuristic guide?
    So are the predictive theories then part of science? or a consequence of science? or a critical component?

    *this point is quite important; depending on how strictly you constrain 'observation, logic deduction and induction', you could argue that pre-historic groups of humans 'did' science - they hunted, they planted and harvested crops, they found and used 'medicinal plants'. This also begs the question of whether the crux of science is the process ('the scientific method') or the outcome ('the body of knowledge acquired') ... or both ... or neither.
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