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B Can you prove anything using the Scientific Method?

  1. Mar 13, 2018 #1
    I am studying the scientific method and have come to the following conclusion.

    Since X -> Y does not imply X is true (or real), it is impossible for the scientific method (SM) to prove that anything is true.

    So like mathematics, the scientific method builds knowledge on axioms which cannot be proven to be true, like mathematics is built on axioms like the point which does not exist.

    The scientific method only stats that "if something is true" then "something else is also true".

    For example: If you push an object -> it will move says the SM. But it does not show that there is a force.
    Another example: "Taking antibiotics" -> "Cures diseases". But it does not tell that disease causing germs exist.

    Is this the correct view??
    Last edited by a moderator: Mar 14, 2018
  2. jcsd
  3. Mar 13, 2018 #2


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    The scientific method is not about "proving" anything, it is about how to develop theories that comport with observations and make predictions about future observations. You never prove anything in physics, that's a math thing.
  4. Mar 13, 2018 #3


    Staff: Mentor

    Yes, this is well known.

    I would say that the scientific method builds knowledge on experimental evidence, not axioms. But experimental evidence verifies or falsifies theories, it does not prove them.

    It definitely does show it. Just because it isn’t proven doesn’t mean that it isn’t shown. And just because it isn’t certain doesn’t mean it isn’t knowledge.

    I think that you are overemphasizing the importance of proofs in the development of knowledge
  5. Mar 13, 2018 #4
    I am a big fan of astronomy and cosmology and astrophysics. Particularly SETI project.

    So, for example when these days scientists discover exoplanets using the SM like this (artist rendition),

    they are saying that the planet is actually there, right??

    Does the SM tell us that the planet is actually there, that it exists ? Because we cannot directly see it using a telescope.
  6. Mar 13, 2018 #5


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    You are putting too much emphasis on the scientific method. OBSERVATIONS (and extrapolations from those observations) tell us that it is there.
  7. Mar 13, 2018 #6


    Staff: Mentor

    Yes, and the evidence shows that the planet is actually there. It doesn’t prove it, but it does show it.

    Directly seeing it with a telescope isn’t proof either.
  8. Mar 13, 2018 #7


    Staff: Mentor

    Leonard Susskind said, "Physicists aren't interested in what is true, but rather what is useful."

    What @phinds said is the kind of useful that Susskind meant.
  9. Mar 13, 2018 #8


    Staff: Mentor

    Et tu phinds!
  10. Mar 13, 2018 #9
    I am a bit confused.

    Because isn't prove and show the same thing.

    In Google I looked at the meaning of "prove" and it says this:
    Prove = demonstrate the truth or existence of (something) by evidence or argument.
    Synonyms = show.

    So, I think they are the same thing right?? To show something is there is also to prove it's there, right?

    Or, when you say "prove" you mean like in the mathematical sense of "proof".

    But when you search for the meaning of "proof" in Google I get the same thing:
    Proof = evidence or argument establishing a fact or the truth of a statement.

    So, when scientists using the scientific method and "show" that an exoplanet exist 1000s of light years away orbiting a star he is in fact giving us "proof" isn't it???
    He is in-fact giving us "evidence or argument establishing a fact which is that a planet exists or the truth of a statement, the statement being that an exoplanet exists".

    So, aren't all (show, prove, proof) the same same thing???

    I feel it is the same thing.

    If not, what is the difference between show and prove?

  11. Mar 13, 2018 #10


    Staff: Mentor

    Yes, I thought that was the sense in which you meant it, particularly given how you used it in the original post. In any case, that is the usual meaning here.

    A proof is the standard form of deductive reasoning. Science is based on inductive reasoning, hence it is not proof as you yourself mentioned in the OP.

    You should re read your own statements regarding “proof” in the OP for context here.
    Last edited: Mar 13, 2018
  12. Mar 13, 2018 #11
    Why is Directly seeing it with a telescope isn’t proof either???

    We don't modify anything when we see things from a telescope, the light is the original light which came from the object, so it has to be real right?
  13. Mar 13, 2018 #12


    Staff: Mentor

    Because it is still inductive reasoning, not deductive. Do you understand the difference between deductive and inductive reasoning? It doesn’t matter how strong the inductive argument is, it does not turn into deductive reasoning
  14. Mar 13, 2018 #13
    Well, I don't fully understand the difference between inductive and deductive reasoning.

    Can you give a real life example of both with regards to Physics??

    Also, is deductive reasoning superior to inductive reasoning?
  15. Mar 13, 2018 #14
    Hi, according to this page: https://www.livescience.com/21569-deduction-vs-induction.html

    the scientific method also uses the deductive approach.

    "The scientific method uses deduction to test hypotheses and theories. "In deductive inference, we hold a theory and based on it we make a prediction of its consequences. That is, we predict what the observations should be if the theory were correct. We go from the general — the theory — to the specific — the observations," said Dr. Sylvia Wassertheil-Smoller, a researcher and professor emerita at Albert Einstein College of Medicine."

    But you said science is purely inductive???
  16. Mar 14, 2018 #15


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    Was it Thomson who gave the toast "The electron: may it never be of any use to anybody!"?
  17. Mar 14, 2018 #16


    Staff: Mentor

    Desuctive reasoning is mathematical theorems or proofs. In science it is the part of the scientific method where you start with a theory and then generate a testable hypothesis. You prove mathematically that if the theory is correct then you will see some hypothesized observation in a given experiment. For example, Noether’s theorem showed that if the laws of physics are time invariant then energy is conserved.

    Inductive reasoning is the part of the scientific method where you perform the experiment and compare the result to the hypothesis. Then, if the data matches the hypothesis you conclude, via inductive reasoning, that the theory is valid, at least in the domain covered by the experiment. For instance, if energy is conserved in an experiment then you would take that as experimental validation of your theory that the laws of physics are time invariant.

    I don’t believe so, I think that both are useful and have their value. The scientific method uses them together to advance knowledge effectively.


    Did I? I don’t think so, but if I did, then my apologies. The inductive part is the part that distinguishes science from other disciplines like math or philosophy that exclusively use deductive reasoning. Science uses both. That is partly what makes it so effective at generating knowledge.
    Last edited: Mar 14, 2018
  18. Mar 14, 2018 #17
    I still don't get this "deductive" part in in science.

    Because you say that "you start with a theory and then generate a testable hypothesis". But, doesn't it happen the other way around. First all you have is the "hypothesis", right?? How can you have a theory first?? Because, from what I understand, a "theory" in science is " a well-substantiated explanation of some aspect of the natural world, based on a body of facts that have been repeatedly confirmed through observation and experiment. ".

    So, I don't understand how you can start with a "theory" and end up with a hypothesis. Is this a special, rare thing in science??

    Is science mainly "inductive"??

    So, did Thompson, and Rutherford, Chadwick discover the atom, proton, neutron and electrons through the deduction process or induction process??
  19. Mar 14, 2018 #18


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    Staff: Mentor

    Part of the issue here may be that "proof" or "proven" can be used to describe the outcome of either inductive or deductive reasoning. Mathematical "proofs" are 100% true (or 100% false) and therefore "proven" whereas scientific theories can never be 100% true but can be said to be "proven" to a lower standard, similar to how a court case is won or lost based on a lower certainty.
  20. Mar 14, 2018 #19


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    It doesn't matter. What matters is that in the end you have a quantitative model that matches observation.
  21. Mar 14, 2018 #20


    Staff: Mentor

    That understanding can confuse you. There are no language police to enforce uniform and consistent use of words like theory, law, hypothesis, and so on. For example, "Newton's Laws" versus "Einstein's Theories of Relativity." Use of law and theory in those contexts are just accidents of history.

    Math can be precise, but natural language will never be precise.
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