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Establishing a basic vocabulary of the philosophy of science

  1. Jul 1, 2007 #1
    Making a basic vocabulary of the philosophy of science

    Hi, I just posted this on another board I'm at that often has debates where issues of science sometimes come up, along with the standard annoying arguments like "it's just a theory". This is an attempt by me to clear things up.

    So, this is what I have so far:

    fact - A scientific fact is a single, specific piece of data, for example "at 10:02:03 PM the 24th of August 1998, while standing in my lab - I let go of a ball. Immediately afterwards, the ball dropped down". That sentence describes two facts which are, like all scientific facts - completely useless alone. But they can provide evidence for and inspire a hypothesis.

    hypothesis - Where facts are specific, a hypothesis is general - for example "whenever you let go of a ball, it will fall". A good hypothesis can be useful because it predicts and explains things. There is a catch, however. All hypotheses depend on Inductive reasoning, in the wide sense of the expression.

    theory - a theory is a well established and thoroughly tested hypothesis.

    induction, in the wide sense of the word - induction in this sense of the word is a kind of reasoning where you make a conclusion about a greater amount of things based on a fewer amount of things. For example, "all the pieces of copper tested so far conducted electricity - this means that all copper conducts electricity".

    Induction isn't 100% reliable - Bertrand Russel has an example of a turkey who, every day observed that the farmer came and gave him food at 9 o clock - and he concluded that the farmer would keep doing so. Which was true every single day until one Christmas morning....

    In spite of this, we blindly entrust our lives to inductive reasoning every day, all the time - because there is often no alternative. Every time you turn on your computer, assuming it won't make it blow up in your face, every time you step off the sidewalk in to the street - assuming it's not just paper painted to look like asphalt, covering a huge abyss. Every time you turn your steering-wheel right, assuming that your car will turn right. In all these cases you're going from a small amount of cases (all the times it's happened before) to a greater amount of cases (all the times it's happened before, and also this time)

    Deductive reasoning - Deductive reasoning usually (if not always) goes from a limited amount of things to an equal or lesser amount of things and is always truth preserving. That means that if the premises are true, then it's a logical necessity that the conclusion is true. For example:

    Premise 1: if cars can transform in to demons, then all pies are tasty
    Premise 2: cars can transform in to demons

    conclusion: all pies are tasty

    Proof - Though most people use this word in a very loose and everyday way - proof, in the specific philosophical sense, only refers to things like the above, where the truth of the reasoning is given through the structure of language, mathematics or logic.

    In science, the reasoning is about and is dependent on the physical world - so a conclusion will be contingent, which means that it's neither logically contradictory nor necessary - you have to check with reality.

    Evidence - A fact in the role of supporting a hypothesis or a theory.

    Falsification - While you'd need to check all copper in the universe to show for certain that all copper conducts electricity, you only need one piece of copper that doesn't conduct electricity to falsify it, that is to prove that it's not true.
    Last edited: Jul 1, 2007
  2. jcsd
  3. Jul 1, 2007 #2


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    Wouldn't it be better to read some books on the philosophy of science and see what vocabulary is already being used rather than making up your own?
  4. Jul 1, 2007 #3
    - I've read two textbooks on the philosophy of science and listened through a 16 hour audio lecture series, in addition to the lectures at my local university. I'm not making it up by myself, at least not completely :p

    Edit: And I am not posting this as some Moses strolling down my mountain - I'm posting it for feedback and corrections!
    Last edited: Jul 1, 2007
  5. Jul 2, 2007 #4
    Soo, either my list is so goddamn perfect and complete, there is no one who sees any reason to comment - or everyone thinks it's so crappy it's hopeless. I wonder which it is :confused:
  6. Jul 3, 2007 #5
    I will help you along a bit.

    Scientific Theory - Not the same as the word 'theory' used in everyday language. National Academy of Sciences defines a scientific theory as "a well-substantiated explanation of some aspect of the natural world that can incorporate facts, laws, inferences, and tested hypotheses.


    From the page, the terms 'fact', 'hypothesis' and 'law' are also defined.

    Proof does not actually exist, even in logic or mathematics. You cannot prove anything ever. Everything in mathematics and logic is proven if the axioms are correct. The axioms is prove if... and so on. This is because the Munchhausen-Trilemma that goes something like this:

    "All justifications in pursuit of certain knowledge have also to justify the means of their justification and doing so they have to justify anew the means of their justification. Therefore there can be no end. We are faced with the hopeless situation of 'infinite regression'. One can stop at self-evidence or common sense or fundamental principles or speaking 'ex cathedra' or at any other evidence, but in doing so the intention to install certain justification is abandoned. The third horn of the trilemma is the application of a circular and therefore invalid argument."

    http://www.physicstoday.org/vol-60/iss-1/8_1.html [Broken]

    The above article explains 'belief', 'knowledge', 'model' and a few other things.

    You explanation of falsifiability is adequate, but ask yourself why hypothesis should be falsifiable to be science. You have only written how to apply the term falsifiability but not why one should apply it. That is something imperative. An interesting book on the subject is The Logic of Scientific Discovery by Karl Popper.

    The astronomer and astrobiologist Carl Sagan made an analogy to stress the importance of falsifiability in his book The Demon-Haunted World - Science as a Candle in the Dark. Below is an excerpt from that book

    A larger excerpt is available here.
    Last edited by a moderator: May 3, 2017
  7. Jul 3, 2007 #6
    I do not think it is consistent to believe that proofs do not actually exist and also to accept falsifiability. From Carl Sagan's words falsifiablity is related to disproof and disproof is a proof for the denial of an assertion. It seems that to believe that proofs do not exist means to disbelieve in disproof and so not to believe in falsifiability.

    In respone to the OP. I think that in your description of deductive reasoning it would be better to remove the first part of the first sentance. That part doesn't fit with my conceptions of deductive reasoning, but that could come from the use of the word thing, and how the relations of "equal to" and "lesser than" work with those things. Maybe change the word thing to something definate, that at least would make things clearer from my perspective.
  8. Jul 4, 2007 #7
    No, disproof is not the proof for the denial of an assertion. Proof/disproof is a false dichotomy as well as true/false.

    Let go of the two terms, as they are not really a part of science. Science only uses the concept of 'falsifiability' and 'approximation', as the other terms are either redundant or trivial.

    An assertion is that event A leads to consequence B. Experiments show that consequence B has occurred. This does not mean in any way that you have proven event A. You can do as many experiments as you wish, but you can never prove it. The more data that supports the assertion, the better is the approximation, but you can never ever prove anything. It is just at some point, when there is a ridiculous amount of evidence, the general public uses the words 'true' and 'proven' for the fact that the earth orbits the sun, but that is in no way part of science or scientific methodology.

    An assertion is that event A leads to consequence B. Experiments show that consequence B has NOT occurred. This means that the initial assertion has been falsified, that is, not a valid approximation and will not be entered as positive scientific knowledge. That does not mean that it is wrong in an absolute sense. Further investigations may reveal more complex interactions.
  9. Jul 4, 2007 #8
    I understand the term assertion to be a proposition put forward as true. I understand proposition to be something capable of truthfulness or falseness. I understand true as something that can be given meaning. I understand denial to be the assertion of the negation of a proposition.

    Given some proposition P, if I cannot prove the truthfulness of P, perhaps I can prove the truthfulness about its denial, ~P. Let the assertion ~P be Q, can I prove the truthfulness now of Q? Which is to ask, can I prove the truthfulness of ~P? Which is to ask, can I prove the denial of P? To offer a proof of the denial of P is not a proof of ~P? And I should not shorten the statement "proof of the denial" with "disproof"? I should not say that to offer a proof of the denial of P is not a disproof of P? I should not say any of this because proof does not exist?

    By this I am of the understanding that you are stating the proposition "Event A leads to consequence B" is true. But then you have already stated to let go of true/false. Letting go of true/false, renders assertion as meaningless because nothing can be a proposition without true/false. By definition "event A leads to consequence B" is an open sentence not a proposition and so fails to be an assertion. Once A and B are given meaning then it can be considered a proposition and then enters the realm of something that can be asserted.

    I still claim:
    I also do not think that it is consistent to not accept the use of the term true and use the term assertion, because assertion is dependant on the term true.

    From my point of view logic and mathematics are at the top of the list of the tools a scientist should use while engaging in a scientific endeavor. Proof should not be dismissed from the OP's list.
    Last edited: Jul 4, 2007
  10. Jul 4, 2007 #9
    'Proof' doesn't exist. Ever. Read the Munchhausen-Trilemma. I have also said that proof/disproof is a false dichotomy. It is only in the rigid system of logic that it makes sense to speak of 'truth' and 'false'. It does not apply to science in the same way.

    The terms 'proof' and 'disproof' are only used in logic, which almost completely disregards the Munchhausen-Trilemma. Logic simply says that something is 'proven' if combinations of axioms leads to that result. In logic, something if 'disproven' if a combination of axioms leads to its denial.

    Even in logic, you cannot really prove something. In order to justify the correctness of your 'proof' (certain knowledge) you need to justify the means of their justification and so on ad infinitum. If you choose to stay at something that seems obvious, like axioms, you are thereby trying to justify something with itself, and therefore a circular and therefore invalid argument. The term 'proof' or 'absolute knowledge' is just logic being full of itself. Science makes no such assumptions and therein lies the difference.

    By falsifying an assertion in science, you are basically saying that the prediction made by the assertion (or the assertion itself) does not match with empirical data. That means that the assertion has not stood up to the test of science and is therefore, in its current state not a good enough approximation and is therefore discarded. Falsification exist in science, disproof does not because science makes no pretense (like logic) to discover absolute truths.

    There is a huge difference between the philosophy of logic and the philosophy of science.

    In science, It does not matter how beautiful your theory is or how nice mathematics it has, if experiments contradicts it, it is falsified (even if it is based on mathematical 'proofs').
  11. Jul 4, 2007 #10
    I think this is important. Are we using the term 'certain' to mean 'absolute' so that 'certain knowledge' is 'absolute knowledge'. A type of knowledge that we could have 100% confidence in? And 'scientific knowledge' does not make a claim to 'absolute knowledge' and so the trilemma does not apply? And that 'proof' does make a claim to 'absolute knowledge' and so the trilemma does apply which by the infinite regression of justification 'proof' does not exist. And finally that this 'proof' that does not exist should be abandoned? Am I close to understanding what you are saying? If not please be specific and tell me where I am mistaken.
    Last edited: Jul 4, 2007
  12. Jul 5, 2007 #11
    Yes, it is correct that science does not make claims of absolute knowledge. It stops its regression at what is obvious (empiricism etc.). The idea of 'proof' and 'disprove' as claims of absolute knowledge should/have been abandoned in science (not necessarily in logic) for falsification and approximation, because they are more honest terms of what science does.

    When logic/math says it has 'proved' something, it is just short for "this is true, provided that the axioms and the combinations of them are true, which is obvious".

    What I'm really saying is that one should be careful of using the terms 'proof' and 'disproof'.
  13. Jul 5, 2007 #12
    I am glad that I at least get the principle of what you are saying.

    I think that this is a very worthy motivation. I am not sure removing terms, people mistakenly interpret, is a proper solution.

    The author of a logic text stipulates clearly how to determine truth values for propostion within the formal context of the logic under consideration. The author also stipulates exactly what proved means within that logic. They do not stipulate how to interpret the truth value of a proposition or stipulate the meaning of proved in the context of 'absolute knowledge'. It is outside of the context of a logic to interpret a proposition as true or false under the umbrella of 'absolute knowledge'.

    I have never happened across an author of a logic text saying that the results of this logic are 'absolute knowledge' and you are now henceforth fully justified as an 'absolute knowledge' generator.

    Terms have technical meanings within contexts. People can make mistakes interpreting terms, especially when the term is taken out of context. Science, math, and logic have terms and any of those terms can be misunderstood, misinterpreted, misapplied, especially when taken out of context.

    I suspect that interpreting 'proof' as 'absolute knowledge' is a misinterpretation of the term 'proof' and so it would be a mistake to infer the result that 'proof' does not really exist. Your result could be right, it could be a proper position to take. But I fail to make the connection from 'proof' to 'absolute knowledge'.

    I agree that we should be careful. Does the idea of 'proof' necessarily lead to a claim of 'absolute knowledge'? If it does, how so?
  14. Jul 6, 2007 #13
    Edit: woah, I didn't see the topic had evolved, I've just had this thread open on a tab for a while and decided to reply without checking. Sorry if I'm saying redundant and useless things here.

    - Heaps o' thanks :smile:

    Scientific Theory - Not the same as the word 'theory' used in everyday language. National Academy of Sciences defines a scientific theory as "a well-substantiated explanation of some aspect of the natural world that can incorporate facts, laws, inferences, and tested hypotheses.[/quote]- In other words, I need to add that theories are even wider than hypotheses... but nothing else? I mean, don't hypotheses also incorporate facts, laws and inferences?

    - Er, would it be appropriate to say that an observation is what I defined fact as above, and then "fact" is a well established observation?

    - Has potential, with some modifications. I'll be back with that later I think.

    - I'm pretty sure that's controversial, so I think I should just point that out. Thanks for indirectly pointing that out.

    - "Knowledge" has been the subject of a fair bit of controversy lately, which she kind of ignores (here's some of it, if you're interested: http://en.wikipedia.org/wiki/Gettier_problem ) - "model" might belong on the list, though.

    - I'm aware of Popper - I was even a fan before I read about Kuhn and onwards - but I think this is moving a bit away from just making a list of loose definitions.
    Last edited by a moderator: May 3, 2017
  15. Jul 6, 2007 #14
    The term 'proof' does not need to translate into absolute knowledge in technical terms (or in logic or science), but it sure does so in the mind of the public. Similar confusion arise when using the word 'theory' for example. In everyday usage, 'theory' means guess, but it does not mean that in mathematics or science. When some outsider says 'this has been scientifically proven' it leads people to automatically to think it as absolute knowledge.

    I think that, in at least science, we should do whatever we can do dispel these misunderstanding. Unfortunately for us, the term 'proof' and 'true' has been misused heavily throughout the development of both science and logic, and their classical definitions invite people to misunderstand them.
  16. Jul 6, 2007 #15
    'theory' is not related to 'hypothesis' in the way you mention it.

    http://www.physicstoday.org/vol-60/iss-1/8_1.html [Broken]

    That articles explains 'hypothesis' quote well.
    Last edited by a moderator: May 3, 2017
  17. Jul 6, 2007 #16
    I agree, and we do not need to conclude that 'proof' does not exist.


    Yes this does happen.

    The motivation you have in helping the general population to better understand science is commendable. Perhaps the problem isn't in the terms but in the way science is presented to the general population through the school system?

    I did a search on science misconceptions.

    The list of misconceptions: http://www.amasci.com/miscon/opphys.html

    Perhaps there isn't a problem with the terms of science but with the people who are involved in educating the general population.

    Last edited by a moderator: Apr 22, 2017
  18. Jul 12, 2007 #17
    - No it's not - at the very least not in formal logic, and it seems reasonable for me to think that that were the terms Popper was thinking on.

    - They are, however, important terms in the Philosophy of Science, which is the topic at hand.

    - Exactly! And I don't think you have any philosopher of science that'd say positive proof figures at the very fundament of science, though it does figure as part of the hypothetico-deductive method (which I'm pretty sure figures in science, certainly it's pretty prominent in the philosophy of science). Negative proof is another matter, of course.

    - We should split this off as a separate topic, I think it could be interesting to delve further into than is appropriate here :smile:

    - I'm quite sure it's used in philosophy as I defined it in the OP - it doesn't necessarily mean absolute knowledge, it just says that the truth is given through language, logic or mathematics, so I don't see why we're debating this in this topic.
    Last edited: Jul 12, 2007
  19. Jul 12, 2007 #18
    - Could you spell out the difference to me, please? I can't really see it from that text.

    Also, note that a physicist who's talking about the nature of science isn't doing physics - she may be doing sociology, psychology, social anthropology or history, she's probably doing philosophy, but either way she's outside her field and it kind of shows :redface:
    Last edited by a moderator: May 3, 2017
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