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Is the theory of evolution a fact?

  1. Sep 13, 2009 #1
    Is the theory of evolution still considered a theory or is it considered a fact now, because of the overwhelming fossil and dna based evidence?

    If so is there a paper, or a journal to cite from that states that evolution is a fact, and not just a theory?
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  3. Sep 13, 2009 #2
    Evolution fits both criteria doesn't it... fact and theory.

    It's definitely a fact because genetic changes have been observed in populations over time, esp. in bacteria. It also has a theoretical framework (natural selection) which attempts to explain how this is happening.

    "Theory" and "fact" aren't progressive rungs on a ladder...theories use the facts to generate explanations and model predictions.
  4. Sep 13, 2009 #3
    thanks for clearing that up
  5. Sep 13, 2009 #4

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    I disagree. Facts without theories to explain them are useless pieces of information. Theories without facts to back them up don't exist, at least not in the scientific meaning of the word "theory".

    Theories are the gold standard in science, better than simple empirical laws. Example of in physics: Newton's law of gravitation and Einstein's field equation are merely empirical laws. General relativity is a theory. GR not only explains how gravity works in terms of the field equation, but derives it. Without the necessary observed facts (the orbit of Mercury, tests of the equivalence principle) GR would just be a hypothesis.

    Evolution is a theory, as good as science can get. It is backed up by logic, by mechanisms (which, BTW, GR is not), and by an immense amount of fact.
  6. Sep 13, 2009 #5


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    Evolution is a fact, its mechanism, that is how and why it happens, is a theory.
  7. Sep 13, 2009 #6
    I was trying reconcile the transition of a theory to a fact. For example, a few hundred years ago it was theorized that earth is round, but nobody knew for sure until Magellan circumnavigated the globe to prove it.

    Should we still speak that in theory that earth is round? or rather it is round as a fact?

    In contrast, the theory of evolution (its mechanics) attempts to explain how life evolved. Massive amounts of evidence supports this "mechanism." Can we now say that evolution is a fact the same way as earth is round?
  8. Sep 13, 2009 #7

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    The problem here is that you are using the word theory in the lay sense.

    That is also a rather bad example. That the Earth was round was a fact known to the ancients.

    Stop abusing the word theory. You seem to think facts are better than theory. They aren't. In a sense, facts are a part of a larger thing called "theory".
  9. Sep 13, 2009 #8


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  10. Sep 13, 2009 #9


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    I think you misunderstood what Bio-student was getting at. The "progressive rungs in a ladder" thing is a common misunderstanding of the scientific process some people have where they think a theory can "graduate" to becoming a fact. That's all Bio-student was talking about. S/he wasn't trying to belittle the concept of a theory.
    Last edited: Sep 13, 2009
  11. Sep 13, 2009 #10
    After looking up a definition of a "theory" as it pertains to science, this is precisely right. I suspected something was out of phase in my understanding, that facts and theory are separate.
  12. Sep 13, 2009 #11
    The new book by Dawkins begins by clearing up this point. He draws the distinction between the two uses of the word "theory" in ordinary English, which I'll abridge:
    1)A System of ideas held as an explanation for a group of facts or phenomena; a hypothesis that has been confirmed by experiment; a statement of what are held to be the general principles of something known or observed
    2)A hypothesis proposed as an explanation; speculation; individual view or notion.

    Dawkins states that evolution is a theory in the first sense. He then goes on to talk about the slightly thorny subject of "proof" in science, contrasting it with maths.
  13. Sep 14, 2009 #12
    Are we talking the very general version found in general bio books, because thats probably written in stone for our life time. The specific modes, and pathways, mechanisms, those things came later and are still subjected to change/improvisions.
  14. Sep 14, 2009 #13

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    The basic concept is what we're after. That the hairy details are subject to change/improvement -- well, that's science. The same is true in physics. High school to freshman physics is predominantly classical physics. That stuff is carved in stone but it is not universally true. Yet we teach it because understanding it is essential to moving on to things like general relativity and the standard model of physics. Are those going to be upended by some future physics? Not really. That new physics will essentially be a refinement to what we already know is true.

    The same goes for biology. The picture up to freshman biology is a simplification. Upper level undergrad is where you start learning the real picture. Is current research going to completely overturn the modern synthesis and genetics? No. Their science is on just as solid a foundation as is ours.

    There are lots of nutjobs out there who are constantly trying to poke holes in everything from classical mechanics to relativity to the LHC. We at PF know those people for what they are: Complete loons. We are flabbergasted every time some doofus of a reporter talks to them, giving them credence. Now imagine a world in which that the loons got more airtime regarding physics than do physicists. That is the world in which biologists live.
  15. Sep 15, 2009 #14
    From the United States National Academy of Science. :) I love it!

  16. Sep 27, 2009 #15
    Ha, good read!
  17. Sep 27, 2009 #16

    Theory >> Fact.

    So saying it's now a fact is paying it a great disservice, and lowering its standing.
  18. Sep 28, 2009 #17
    oh? philosophical can of worms really.
  19. Sep 28, 2009 #18


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    Yes, it's a fact as much as anything is.

    In the sense that if you're writing a paper in biology or biochemistry or any other area where evolution might come into it, you don't provide a citation for 'evolution'. They don't write "assuming the theory of evolution is valid" or any such thing. Most papers in biology would be invalid in part or in whole if evolution wasn't.

    Evolution is not a specific area of biology - it affects everything. And there is no alternative science of biology that studies the subject under the assumption that evolution is false.
  20. Sep 29, 2009 #19

    thtas because evolution is soo strong. Nothing can really compete with it. Unless you call creationism a 'competitive scientific theory' :wink:
  21. Sep 29, 2009 #20
    Adding to my last post from page 1, and asking viewers to please review the link below and explore to the left of that website the information available. Please note that this information is from the United States National Academy of Sciences.:biggrin:

    Also, we should remember as stated by the National Academies of Science , "Because they are not a part of nature, supernatural entities cannot be investigated by science. In this sense, science and religion are separate and address aspects of human understanding in different ways. Attempts to pit science and religion against each other create controversy where none needs to exist." (see Science and Religion to the left of the page within the website above. THX)
    Last edited: Sep 29, 2009
  22. Oct 2, 2009 #21
    There is no such transition between a theory and a fact.

    Scientific theories are the crown jewels of science, much stronger than a mere fact. A theory when used in its scientific context is defined as a well-supported explanation to some parts of the natural world that includes facts, laws, inferences and tested hypotheses.

    When we typically speak of the fact of evolution, we mean anything between shift in allele frequencies and universal common descent. When we speak of the theory of evolution, we mean things like natural selection. Natural selection is of course a "fact" in the trivial, every day sense of the word ("real").
  23. Oct 2, 2009 #22
    Not just papers, a surprising amount of things (some) humans use every day would be invalid such as paternity testing, key methods in forensic medicine and so on and so forth just to name a few.
  24. Oct 6, 2009 #23
    "Evolution is a fact" is a theory.

    "Evolution is a theory" is a fact.


    "Evolution is not a specific area of biology - it affects everything. And there is no alternative science of biology that studies the subject under the assumption that evolution is false. "

    The above may be true of 'micro-evolution' but does it hold true for the theory of 'macro-evolution'? No scientific or medical discovery ever relied on 'macro-evolution' theory, only religious debate has ever resulted from it.
    Last edited: Oct 6, 2009
  25. Oct 6, 2009 #24


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    There is no such distinction in science. Only creationists distinguish "micro-evolution" from "macro-evolution". I've yet to hear even a sound distinction between the two.
  26. Oct 7, 2009 #25
    Hurrah! More proof (were it needed) that 150 years of scientific theory and experiment can be fatally undermined by bon mot. Yay for inference by droll rhetoric. Shame only half of it is true.

    It is indeed a fact that evolution is a theory; a conceptual framework supported by evidence. But in what sense is the statement "evolution is a fact" a theory? It's neither a coherent group of general propositions used as principles of explanation for a class of phenomena; nor is it a proposed explanation whose status is still conjectural, in contrast to well-established propositions that are regarded as reporting matters of actual fact; nor a body of principles, theorems, or the like, belonging to one subdiscipline of mathematics; nor the branch of a science or art that deals with its principles or methods, as distinguished from its practice; nor a particular conception or view of something to be done or of the method of doing it; nor a system of rules or principles; nor contemplation or speculation; nor guess or conjecture.
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