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  1. 11 Jul '16 01:16
    I’m going to be perhaps a bit simplistic in order to avoid bias—

    Are the facts what you observe? Or are the observations themselves what you consider facts? If your observations turn out to be incorrect, do you say that the facts are wrong; or that the observations did not accurately capture the facts?

    Corrections as to how I have presented the questions, as well as filling out the proper nuances are welcome. Thanks.
  2. Standard member DeepThought
    Losing the Thread
    11 Jul '16 06:19
    Originally posted by vistesd
    I’m going to be perhaps a bit simplistic in order to avoid bias—

    Are the facts what you observe? Or are the observations themselves what you consider facts? If your observations turn out to be incorrect, do you say that the facts are wrong; or that the observations did not accurately capture the facts?

    Corrections as to how I have presented the questions, as well as filling out the proper nuances are welcome. Thanks.
    Good question. A case example I used in a different thread was the discovery of the Higgs Boson. The observation was of a pair of photons with combined energy 125GeV, or was it? What was actually observed was the detector behaving in a particular way which the Cern people's "theory of the detector" tells them means that two photons with that combined energy and originating from the same source were detected. They then inferred the photons came from the decay of a Higgs Boson.

    All observations of the world are mediated. When I look at something what is actually happening is that light is bouncing off the thing, hitting my retina which generates a signal to my brain whose visual cortex does a lot of processing on. So my "experience" of seeing the thing is not a direct experience, the only direct experiences are of one's own mental states. I directly observe a mental state, my theory of that mental state is that it means that "I see the thing" and that there is a thing I am looking at. The theory is built in, it's in a slightly different category to a theory I can communicate. The theory about the world (I have the experience of a mental state of seeing a thing, so there must be a thing) is an intuitive one, not a string of symbols which is what we normally think of a theory as being. Like a "string of symbols" type theory it could be wrong - the senses can be deceived. But the mapping between the world and our mental states must be pretty good because the world is pretty unforgiving to beings that cannot interpret their senses of the world well; they get eaten.

    So yes, at that level of description even what one thinks one sees is a theory about the world. However it's so reliable that (modulo consensus between observers, optical illusions, insane people, etc.) there is no real point in doubting it except as an exercise for undergraduates. Similarly, the "theory of the detector" is extremely good and well tested. So much so that although what was actually directly observed were mental states belonging to the operators of LHC, the theories of causation of those mental states (i.e. that it actually happened) are so reliable that we can say, with as much certainty as one can say anything, that the detectors actually did do what they did and there really were two photons which actually did come from the decay of a scalar particle.

    The interesting little point is that this was scientific verification, not falsification. The only thing that was falsified was a null hypothesis (there is no scalar at that energy). The Higgs is necessary for the electro-weak theory (it needs a symmetry breaking mechanism for technical reasons) and the electro-weak theory is the only real candidate, so discovering the particle verifies the theory. As an argument about what one can really know Popper's critical realism is fine, but as a practical way of doing science it doesn't really describe what happens.
  3. 11 Jul '16 12:13 / 1 edit
    Originally posted by DeepThought
    Good question. A case example I used in a different thread was the discovery of the Higgs Boson. The observation was of a pair of photons with combined energy 125GeV, or was it? What was actually observed was the detector behaving in a particular way which the Cern people's "theory of the detector" tells them means that two photons with that combined ...[text shortened]... ealism is fine, but as a practical way of doing science it doesn't really describe what happens.
    Thanks, DT. With all that, if an observation (or set of observations) turns out to be incorrect, do you say that the facts were wrong--or that the observations did not accurately reflect the facts? My question has to do with how those two terms are commonly used in scientific (as opposed to philosophical or mundane discourse)--before the level of hypothesis formation.* Specifically, would a physical scientist normally say that what they (are attempting to) observe are facts, understood as what is the case in the real world? Does it depend on the science (e.g., biology versus physics)?

    It has been argued to me in another thread that science uses the term "fact" fundamentally differently than philosophy (think Wittgenstein), and everyday usage. I just want to see if the "language game" of the physical sciences is that different (or, again, if it depends on which area of scientific inquiry one is talking about)?

    Thanks.

    _____________________________________

    * I realize that at least provisional hypothesis formation might come before observation; on the other hand, I know a research biologist who believes that all research should start out without any a priori constraints--but that might just have been a function of the kind of research he did.
  4. Standard member sonhouse
    Fast and Curious
    11 Jul '16 13:26
    qOriginally posted by vistesd
    Thanks, DT. With all that, if an observation (or set of observations) turns out to be incorrect, do you say that the facts were wrong--or that the observations did not accurately reflect the facts? My question has to do with how those two terms are commonly used in scientific (as opposed to philosophical or mundane discourse)--before the level of hypothes ...[text shortened]... y a priori constraints--but that might just have been a function of the kind of research he did.
    We don't use 'facts' to describe observations ever. An observation is a data point and that is all. If say 1000 of these observations all point to one direction scientifically, then that data set may be enough to make a general statement about that set with such and such probability. Mostly science uses probability since there are almost no absolute facts about anything.

    If it's one thing we have learned from studying quantum physics over the past 100 years or so its that NOTHING is certain.

    For instance, we cannot tell the exact energy of a particle AND the exact position at the same time and the more exact the one we figure out, the less exact the other gets, so we can make statements about the exact position of the particle but the exact energy cannot be known BECAUSE we took pains to make the position known as exactly as we could.

    This is the heart of the 'quantum uncertainty' principle and it has been known for generations of scientists.

    It turns out we can squeeze one parameter to get better results in some way, such as LIGO, the gravity wave observatory that just detected gravity waves twice in the past few months.

    There is an upgrade coming in that will double the sensitivity of the system based on the quantum squeeze effect where we can get better sensitivity at the cost of some other parameter, where that other parameter is in part of the system that doesn't matter to the overall performance.

    But you can carry such compromises only to a certain extent and after that you get diminishing returns but in the case of LIGO it allows sensitivity achievable in no other way except make the optical path legs a lot larger and that takes a lot more money than getting tricky with quantum physics
  5. 11 Jul '16 14:46
    Originally posted by sonhouse
    If it's one thing we have learned from studying quantum physics over the past 100 years or so its that NOTHING is certain.

    For instance, we cannot tell the exact energy of a particle AND the exact position at the same time and the more exact the one we figure out, the less exact the other gets, so we can make statements about the exact position of the pa ...[text shortened]... energy cannot be known BECAUSE we took pains to make the position known as exactly as we could.
    I disagree with this view of quantum mechanics. Quantum mechanics is actually arguably our most successful theory in terms of accurately describing the world. That those descriptions don't intuitively fit well with our understanding of the macro world, is not an indication of its failure or even a lack of certainty at the micro scale. Some quantum properties such as mass or wavelength can be measured with extreme accuracy, and in some cases quantum mechanics predicts masses to extreme accuracy.

    As for the topic of the thread, the word 'fact' is used with a rather wide range of meaning even in science.
  6. 11 Jul '16 16:01 / 1 edit
    When thinking and speaking rigorously, I take the verbal utterance that rhymes with "phakt" and in writing is spelled f, a, c, t, to denote that which is the case. But the utterance is not the fact. However, informally I sometimes refer to the utterance as the fact.

    People may agree with the rigorous usage, or not. It makes communication easier if we agree.
  7. Standard member sonhouse
    Fast and Curious
    11 Jul '16 16:42
    Originally posted by twhitehead
    I disagree with this view of quantum mechanics. Quantum mechanics is actually arguably our most successful theory in terms of accurately describing the world. That those descriptions don't intuitively fit well with our understanding of the macro world, is not an indication of its failure or even a lack of certainty at the micro scale. Some quantum propert ...[text shortened]... opic of the thread, the word 'fact' is used with a rather wide range of meaning even in science.
    It's entirely possible we as humans will never be able to completely figure out quantum physics.

    Maybe human plus silicon can do it, a life changing world would appear if we do. Prove the possibility of worm holes, time travel and all that.

    Non-zero energy is going on that we don't fully understand yet. I say yet because I feel we will figure it out in time.
  8. 11 Jul '16 17:02
    Originally posted by sonhouse
    It's entirely possible we as humans will never be able to completely figure out quantum physics.
    Most of the mathematics of it was figured out a long time ago and is pretty rigorous. There is more to be discovered and figured out, but it seems a bit overkill to suggest that quantum physics as a whole is not understood. The biggest problem is that it is largely non-intuitive so it cannot easily be taught without actually learning the mathematics and equations.
  9. 11 Jul '16 18:07
    Originally posted by sonhouse
    It's entirely possible we as humans will never be able to completely figure out quantum physics.

    Maybe human plus silicon can do it, a life changing world would appear if we do. Prove the possibility of worm holes, time travel and all that.

    Non-zero energy is going on that we don't fully understand yet. I say yet because I feel we will figure it out in time.
    What does it mean to "completely figure out" something?
  10. 11 Jul '16 18:29
    Originally posted by KazetNagorra
    What does it mean to "completely figure out" something?
    to think about it without a blank cross-eyed face?
  11. Standard member DeepThought
    Losing the Thread
    11 Jul '16 18:44
    Originally posted by vistesd
    Thanks, DT. With all that, if an observation (or set of observations) turns out to be incorrect, do you say that the facts were wrong--or that the observations did not accurately reflect the facts? My question has to do with how those two terms are commonly used in scientific (as opposed to philosophical or mundane discourse)--before the level of hypothesi ...[text shortened]... y a priori constraints--but that might just have been a function of the kind of research he did.
    First, I don't think the word "fact" has any special meaning in Science that it does not have in other fields. Second it's not a word scientists use particularly, certainly no more than any other group - they'll talk about experiments, evidence and so forth, but will rarely talk about a "scientific fact" - certainly not when discussing their work with each other. I think the two groups of professionals who use the word "fact" most are lawyers and politicians, the word tends to have more of a rhetorical purpose than a descriptive one so it's more important to fields which involve rhetoric. When it is used in Science it has the same meaning as in ordinary usage.

    According the the Oxford online dictionary, the etymology is as follows:
    Late 15th century: from Latin factum, neuter past participle of facere 'do'. The original sense was 'an act', later 'a crime', surviving in the phrase before (or after) the fact. The earliest of the current senses ('truth', 'reality' ) dates from the late 16th century.

    http://www.oxforddictionaries.com/definition/english/fact
    So the word comes from law and, except for the "after the fact" sense, won't be used in science any differently to the way it is used in law.

    I was trying to think what it is about a fact that makes it a scientific fact and not just any old fact. Since a fact is a statement about the world and science makes statements about the world all facts would seem to be scientific. The adjective scientific must therefore refer to the fact that the fact is true in order to be a fact. So, it must be that the fact has undergone a truth test that is scientific - which in science would be an experiment. So in the event that "fact" has any distinct meaning in science it is simply to do with the verification method.

    What happens when the facts change? A little over half a century ago they had worked out the age of the universe and it came out to less than the age of the Earth. Clearly something was wrong. It turned out the problem came because there were two types of Cephid variable. A Cephid variable is a kind of star that changes in brightness over time. The absolute magnitude of the star depends on the rate of pulsing, which makes Cephid variables useful as standard candles. Because this relation is different for the two and that was not taken into account the estimate for the age of the universe was too small and fortunately obviously so. In that case there was a fact missing, which threw out the result. The result (that the Earth is older than the Universe) was never mistaken for a fact because it was clearly faulty. But had it been then it would have been revealed as a false fact.

    The truth test for an actual experimental data point is just whether we trust the experimenter to tell the truth and perform their experiment competently. The result isn't really certain until the experiment has been repeated by more than one group, which cuts out bad results due to bad experimental design, general incompetence, and fraud. So, except that scientists do not present their results under oath but have a different system to avoid deliberate falsehoods, the truth test for whether the raw data is true is not really any different to the one used in a trial - the witness is assumed to be trustworthy until their evidence is contradicted by someone else's or there is some evidence that they are not.

    So, I think that the word "fact" has the same meaning as in philosophy and ordinary usage. When facts turn out to be wrong, as can happen, then the old facts are no longer viewed as facts and the new facts replace them. Formally the old facts weren't ever facts. Because we live with imperfect truth tests, and natural languages are loose, scientists like any other group, will talk about facts being wrong. This is just an informal usage of the word fact. What they really mean is that the old statements were mistaken for facts, but in fact were not.

    Scientists observe objects and their phenomena, they do not observe facts. A fact is a sentence and cannot be observed, the thing the fact is about is what is observed, unless one counts reading it as observing a fact. If a scientist claims to have observed a fact it is because the word has no specific technical meaning in science and so scientists are as likely to be as hazy about the correct meaning of the word as any other group of people.
  12. 12 Jul '16 08:29
    Originally posted by DeepThought
    Scientists observe objects and their phenomena, they do not observe facts. A fact is a sentence and cannot be observed, the thing the fact is about is what is observed, unless one counts reading it as observing a fact.
    Until this point in your post, it was ambiguous whether or not you considered a fact to be a sentence about something or the actual thing it refers to, although I was leaning strongly towards the latter, and thing you would struggle to actually justify the former from your own usage.

    If a scientist claims to have observed a fact it is because the word has no specific technical meaning in science and so scientists are as likely to be as hazy about the correct meaning of the word as any other group of people.
    There is no 'correct meaning'. There are multiple meanings, and as you say, most people are a little hazy about it - thus making the hazy meaning the 'correct meaning'.

    The only time where the two popular meanings come into conflict is when you ask whether a fact was a fact before anyone knew about it - or whether facts can exist that are never known.
  13. Standard member DeepThought
    Losing the Thread
    12 Jul '16 10:42
    Originally posted by twhitehead
    Until this point in your post, it was ambiguous whether or not you considered a fact to be a sentence about something or the actual thing it refers to, although I was leaning strongly towards the latter, and thing you would struggle to actually justify the former from your own usage.

    [b]If a scientist claims to have observed a fact it is because the wo ...[text shortened]... a fact was a fact before anyone knew about it - or whether facts can exist that are never known.
    No, I don't think I was at all ambiguous, the following sentence is the third one after the quotation from the Oxford online dictionary: "Since a fact is a statement about the world and science makes statements about the world all facts would seem to be scientific.", I do not see how this can be regarded as ambiguous.
  14. Standard member sonhouse
    Fast and Curious
    12 Jul '16 11:50 / 1 edit
    Originally posted by DeepThought
    No, I don't think I was at all ambiguous, the following sentence is the third one after the quotation from the Oxford online dictionary: "Since a fact is a statement about the world and science makes statements about the world all facts would seem to be scientific.", I do not see how this can be regarded as ambiguous.
    In science i don't think you can use fact, as in 'it is a fact there will never be teleportation like star trek' since we cannot know the future of science. We can say 'it is highly unlikely for there ever to be teleportation like star trek' or something like that but you can't just say something is a fact about future tech.

    You can say I suppose, 'its a fact that water at STP boils at 100 degrees C' but then you would have to qualify that, specifying ordinary water and not heavy water which boils at around 101 degree C.

    So you would have to be very careful using the word 'fact'.

    You might be able to say 'its a fact if you are at ground zero of a 1000 ton meteorite you will die when it lands on your head'.
  15. 12 Jul '16 13:17
    I'll check back to see what else is said, but thanks for your help guys.