Talk:Evolution as fact and theory

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Formal inference?[edit]

I see Dave has reinstated the phrase "formal structure of rational inference" in the lead and there may be a substantive disagreement in the offing, so I will state my views here on the Rational Inference section, which I was planning to remove from the article.

In most scientific discourse it's accepted that a theory cannot be proved in the way that, say, a mathematical theorem can be. At best one can show there is no important refutation. I don't see that the introduction of abduction or any other technical mechanisms change this situation. As Peirce admitted, in abduction one is guessing one part of the inference, and the the role of testing is in no way solved: it has to be done the old way by seeing whether the theory produces consequences that are at variance with experiment. I also don't know of evidence that Darwin was using any system of induction: he seems to be closer to a Humean empiricist.

Clearly biologists would like their subject to be as formal as physics. But the key to that is to state the theories in some formal language, not to use some new inference strategy that is supposed to prove what cannot be proved. I'm not a biologist and though I've read as many of the cited works as I can, I'm not convinced that they say anything new that changes things. If they do, can someone enlighten me?

More generally, does anyone believe that the section "The Evidence" adds anything useful to the article? It's got some good stuff there, and if anyone could suggest a more suitable place in WP to put it, I'd be grateful. Chris55 (talk) 18:01, 24 February 2013 (UTC)

No problem about removing "formal structure of rational inference" from the lead or from the article, I was just trying to summarise what was there.
As for Darwin's method, Ghiselin writes "Darwin's claim, in the Introduction, that he worked by patiently accumulating facts before allowing himself to speculate must be taken with a block of salt. Rather than following the "Baconian" approach that was widely popular in his day, he took theory as his guide, using the facts to test hypotheses. The approach that he used was more in line with what has been called the hypothetico-deductive approach, or as some would say, the argument to the best explanation."
Based on Bowler's 2003 edition of Evolution: The History of an Idea pp. 179–180, 197–198, we have in On the Origin of Species that "Darwin's scientific method was also disputed, with his proponents favouring the empiricism of John Stuart Mill's A System of Logic, while opponents held to the idealist school of William Whewell's Philosophy of the Inductive Sciences, in which investigation could begin with the intuitive truth that species were fixed objects created by design." From Desmond and Moore I recall the idea that Darwin was trying to meet Whewell's standards of consilience.
Evidence might fit better in evidence of common descent. Hope that helps. . dave souza, talk 18:53, 24 February 2013 (UTC)
Thanks. Since Whewell attended Henslow's soirées and classes together with Darwin it seems quite likely that Darwin attended some of his classes and it certainly describes Darwin's methods.
A smaller point: I did think it important to point out that clarifying the terms being used doesn't automatically solve disagreements between different sides, but you removed that sentence. I was thinking of adding some comments in the literature section to illustrate this point. Chris55 (talk) 19:44, 24 February 2013 (UTC)
Yes, Charles Darwin's education#Natural theology and geology convinced him of the methodology of Herschel's Preliminary Discourse and inductive reasoning. I don't recall anything suggesting Darwin attended Whewell's classes as such, but the lecture setup was much less formal at Cambridge at that time.
On the second point, your line about disagreements between "scientists and educators on the one hand and creationists and proponents of intelligent design, who cannot accept it, on the other" seemed to me to suggest a false equivalence, almost giving equal validity, and there's a whole can of worms there that this article doesn't really explore as far as I can see. I'm reading Pennock, who makes the point on page 7 of his Tower of Babel about the same terms having different meanings so the meaning has to be understood to understand the disagreement. From p 49 onwards he discusses YECs who believe there can be no proof of evolution, as they have the notion of "proof text" meaning a biblical quotation which is proof of God's understanding on a topic, and more generally many creationists believe that absolute certainty is needed for proof. I think exploring creationist mindsets may be beyond the reasonable scope of this article. . . dave souza, talk 21:48, 24 February 2013 (UTC)
The only equivalence I can see between the two sides is the roughly 40/40 split in the American opinion polls (with 20% undecided) on the central issue of human origins. Certainly it's not as bad in the rest of the world, but it seems something one needs to acknowledge. It's easy to dismiss that side as ignorant, bigoted or duped but that doesn't seem to make it go away. I see some progress in that increasingly creationists accept "micro-evolution" even when they don't accept the whole thing and it seems that the ID debate has moved the central issue away from "7 days" to the point that that emphasis might be quietly demoted. I know who I would trust between the two sides but it seems that many Americans have the opposite allegiance. I agree it's not the place to explore this issue further and at the moment I'm still trying to understand Wallace's 'heresy'. I don't find Flannery's line convincing. Chris55 (talk) 09:05, 25 February 2013 (UTC)
As Pennock notes, the "7 days" issue is theological, between literalist YECs and OECs like Hugh Ross as much as a YEC dispute with science. The ID position accepts either, while focussing on trying to change the definition of science to accept their supernatural explanations. The old creation science two-model theory that if they can find a problem with evolution, that means that Goddidit. I don't think we need to provide an index to creationist claims, at the most all we need is a link to the creation-evolution controversy. As for Wallace's 'heresy', it doesn't seem to be mentioned now in this article. Probably Wallace's spiritualism, which disappointed Darwin, though Wallace remained a staunch proponent of natural selection as the main cause of evolution. They also differed about sexual selection, but I think that was a minor disagreement. . dave souza, talk 20:08, 26 February 2013 (UTC)

Darwin wrote specifically on adopting Whewell's philosphical principles. The recent gerrymandering of this article now contradicts much of the actual scientific philosophy that Darwin and other evolutionists have applied and written on the subject matter. "In most scientific discourse it's accepted that a theory cannot be proved in the way that, say, a mathematical theorem can be." - false. Sounds like a made up idea from someone who has not read very deep into the philosophy of science. "But the key to that is to state the theories in some formal language, not to use some new inference strategy that is supposed to prove what cannot be proved." - what is this gobblygook? (talk) 19:04, 26 February 2013 (UTC)

Where did Darwin write specifically on adopting Whewell's philosphical principles? The only mention of Whewell in OtOOS is the title page quote, which doesn't say that. Proof is for maths and whisky, inductive proof is a weight of evidence: perhaps we can expand on that point. . dave souza, talk 19:59, 26 February 2013 (UTC)
"As Whewell, the historian of the inductive sciences, remarks:—"Hypotheses may often be of service to science, when they involve a certain portion of incompleteness, and even of error." Under this point of view I venture to advance the hypothesis of Pangenesis, which implies that every separate part of the whole organisation reproduces itself. So that ovules, spermatozoa, and pollen-grains,—the fertilised egg or seed, as well as buds,—include and consist of a multitude of germs thrown off from each separate part or unit." (Charles Darwin - [1]) He mentions him elsewhere. (talk) 21:10, 26 February 2013 (UTC)
Nice find, but I don't think he's "adopting" Whewell's principles. At Cambridge Darwin had learnt the scientific approach of Herschel and Whewell, and he was concerned to justify his work in these terms, but effectively developed his own methods. In this case, he is "aware that my view is merely a provisional hypothesis or speculation; but until a better one be advanced, it will serve to bring together a multitude of facts which are at present left disconnected by any efficient cause." And of course pangenesis didn't really serve very well. Similarly, "we can perceive that events are brought about not by insulated interpositions of Divine power, exerted in each particular case, but by the establishment of general laws" is used to justify Darwin's use of what Whewell apparently called the hypothetico-deductive model, but the result was favoured by supporters of Mill, and opposed by followers of Whewell. So, don't think that's very conclusive. . . dave souza, talk 21:59, 26 February 2013 (UTC)
As I stated - he mentions Whewell elsewhere. See also here [2] for a paper that discusses Whewells influence on his development of evolutionary theory. The point was simply to show that Darwin was aware of Whewell - not to propt his theory of pangenesis, which has not been completely rejected [3] - especially when read properly. (talk) 22:12, 26 February 2013 (UTC)
An interesting paper, but raises some red flags and doesn't seem to address "use and disuse inheritance" which Darwin had hoped to explain. Has this thesis been taken up by others? . . dave souza, talk 22:34, 27 February 2013 (UTC)
"As a graduate of the University of Cambridge (Newton's alma mater) and a friend and protege of Whewell, Darwin knew full well that the best kind of science is that which has a cause at its heart, one which ties all together in a unified whole...Sedgwick and Whewell, the very men who had led Darwin into a life of Science."[4] - Sounds like Michael Ruse found Whewell to be fairly important in Darwin's philosophy corroborating my earlier claim. (talk) 01:40, 27 February 2013 (UTC)
Rather a dispute about what counts as a vera causa, we may be covering the same point in differing words: I'd just note that Darwin started from the methodology of Herschel and Whewell, and of course Henslow, rather than "adopting" that philosophy. Anyway, this has been useful for other articles and I've found other mentions of the topic, but it's not really relevant to this article as far as I can see. . . dave souza, talk 22:34, 27 February 2013 (UTC)

Material moved[edit]

Return previous lead[edit]

The previous lead was put together collaboratively after a lengthy discussion.(see [5] Multiple editors of the main evolutionary article worked long and hard to put the original lead together. The current lead is nowhere near to the standard of excellence that was posted through the collaborative efforts. (talk) 22:49, 26 February 2013 (UTC)

The current lead is filled with errors - it would require a gargantuan effort to edit it back to the quality that was there previously. Someone came in and changed this without collaboration claiming that the work in here was not part of a collaborative effort - contrary to the archived records. Restore the work please - or I will do it. (talk) 22:52, 26 February 2013 (UTC)
I restored the old lead. If someone wants to change it - please consult your edits here in the discussion pages prior to making major revisions. The current lead was organized and put together collaboratively with a lot of input from many editors. (talk) 22:59, 26 February 2013 (UTC)
That the previous lead was put together via collaboration doesn't mean it can't be changed (and further collaborated on). WP:BOLD specifies that an editor may make bold changes to the article. Within what you've written above, I see no actual objection to the content of the new lead, so I have restored it. If you have an objection to the content, and not to the bold nature of the change, then please specify what problem you see so it can be addressed. Thanks.   — Jess· Δ 23:59, 26 February 2013 (UTC)
The problems were already addressed in the discussion that took place as referenced in the archives - please review the archives - [6]. Do we really need to repeat all that history here? Many of the points in the archived thread take issue with some of the points created in the new lead. I was WP:BOLD in returning the lead back to its original form. The current lead is a mess. (talk) 00:34, 27 February 2013 (UTC)
  • Error 1: "A scientific theory is a well-substantiated explanation of such facts." - Not so. There have been many scientific theories that have been falsified, hence they were not well-substantiated. Science builds off unsubstantiated theories - Popper has even made this claim in reference to the ancient greek theories of Thales and Anaximander. Although, they were not scientific theories, they certainly contributed to other scientific theories.
  • Error 2: "The facts of evolution come from observational evidence of current processes, from imperfections in organisms recording historical common descent, and from transitions in the fossil record." - what are imperfections in organisms recording common descent? I did not know that there were imperfections in organisms that were recording data on common descent - those are some brillian imperfections? Perhaps they are humans?
  • Error 3: "Evolution means change over time, as in stellar evolution." - Can something change without time? "The simple assertion that past, present, and future differ from one another is not in itself an evolutionary world view." (Levins and Lewontin, 1985)
  • Error 4: "In biology it refers to observed changes in organisms, to their descent from a common ancestor, and at a technical level to a change in gene frequency over time; it can also refer to explanatory theories such as Darwin's theory of natural selection which explain the mechanisms of evolution." That's a hodge podge of statements! Evolution does not refer to observed changes in organisms, because if that were so we would call metamorphosis evolution and it is not. Descent from a common ancestor is probably the only correct part here. Change in gene frequency over time - meh, okay, but kinda empty in meaning. Now we have explanatory theories - what other kinds of theories are there? Grammar alert "explains the mechanisms", plus the sentence is empty because it says nothing about what those mechanisms are, nothing of what natural selection is, and is natural selection a theory or is evolution? Natural selection is a three part syllogistic mechanism that explains how adaptations are preserved.
  • I can go on - the grammar is attrocious, the science is high school, and it in no way compares to the previous lead that was placed here through collaborative effort and extensive research. Granted, the previous lead required some editing and simplification - but to swipe it clean and replace it with this stuff!? Unjustified. (talk) 02:02, 27 February 2013 (UTC)
1. The definition is taken from the Wiki page which is in itself sourced from the NAS I believe. It's widely accepted as a definition and there are of course many exceptions. This does not ignore the well-known contributions of Popper, Kuhn, Lakatos etc.
2. I don't recognize the phrase but it is a well-known rebuttal of the Paley argument by design.
3. I didn't put that there.
4. Again that has been altered since I put it there.
I won't be contributing to this discussion as I'm away from the net for a few days but I'll be interested to see the results. Chris55 (talk) 09:47, 27 February 2013 (UTC)
"from imperfections in organisms recording historical common descent" Is refering to things like Mitochondrial Eve Y-chromosomal Adam and mutations/deactivated genes/retroviruses that can be used to determine decent and time since divergence. — raekyt 13:20, 27 February 2013 (UTC)

Defining evolution[edit]

As discussed above, Casey Luskin is a useless source for science, and the article did not reflect his anit-evolution claims. I've added another article by Moran as a source to clarify what evolution means generally, and specifically in biology, and have revised the wording a little to comply closely with Moran's article cited previously. He covers the points listed, albeit not in a simple checklist. I've tried looking at other sources, but haven't found any better reference for this specific set of definitions. The 1998 NAS report we reference covers similar issues, again not as a chacklist. They have a 2008 edition which gives a description, but again no checklist as far as I've found. . dave souza, talk 14:09, 10 March 2013 (UTC)

Thanks Dave for producing a more relevant citation for the meaning of the word "evolution" (Moran1993a). It enlightens me as to the origin of views commonly expressed in evolution-related articles in WP.
It's interesting that Moran flays into all the dictionaries: Oxford Concise Scientific, Websters, Chambers etc and indeed ignores the elucidation by Futuyma that he himself quotes and is in the article. The current Oxford "Pro" dictionary defines evolution as "the process by which different kinds of living organism are believed to have developed from earlier forms during the history of the earth", which may avoid the obvious shortcomings of the Oxford Scientific. But that is rather different to the "genetic" definition on which he depends. He says "Recently I read a statement from a creationist who claimed that scientists are being dishonest when they talk about evolution. This person believed that evolution was being misrepresented to the public. The real problem is that the public, and creationists, do not understand what evolution is all about." I think that attitude is condescending and self-defeating.
Unfortunately, by changing a list of definitions into one of "well-established facts" you have begged the point of the whole article, in particular no. 2: "All life forms have descended with modifications from ancestors in a process of common descent".
I still believe that Luskin's point is valid and I'm sorry you're unwilling to admit it: people are talking past each other partly because they are using the word "evolution" in different senses. This article is about the public perception of science. Gould, who in the absence of older citations I still believe to be the originator of the phrase used as the title of this article (Dobzhansky has his own article), was writing a popular article: one that in religious circles would be called "apologetic". By refusing to acknowledge these differences you are in danger of making scientists appear as obdurate as religionists. Chris55 (talk) 18:22, 10 March 2013 (UTC)
We do have some sources for the point that public ideas of evolution differ from current scientific thought, but as Moran notes, creationists sometimes hold to very different meanings. Luskin is clearly trying to put over a particular creationist view that microevolution or evolution within species is ok, but do we want to cover that in this article? The Oxford's use of "believed" looks very odd if it's describing science. . dave souza, talk 22:50, 10 March 2013 (UTC)
I've tracked down the original source of Luskin's definitions, which is Thomson, Keith Stewart (1982). "The meanings of evolution". American Scientist 70: 529–531.  The author was a professor of biology at Yale. Is this an acceptable citation? Chris55 (talk) 20:25, 10 March 2013 (UTC)
Hmm. It's certainly better than Luskin, and gives one view of the position in 1982, but is showing its age a bit. I think most scientists now accept that avian dinosaurs aren't extinct! Apart from the slightly archaic language, it's surely wrong to say that "the third meaning is currently confined to a particular explanatory hypothesis, Darwinism." Not a neutral statement. A fourth meaning would be evolution as progression, a common idea but not one considered part of the modern evolutionary view. The idea that evolution means "change over time" is accurate, but not sure if it's illustrated by the article: is breeding of dogs evolution? So, I think there are some issues with this, and it would be good to get a better source giving a more up to date picture. . dave souza, talk 22:50, 10 March 2013 (UTC)
I agree it's reflecting past controversies, but I thought his comment on dinosaurs--"it's only hypothesis...that they became extinct at the end of the Cretaceous" was quite perspicacious. Wikipedia doesn't demand that citations should be neutral, and would Darwin have been a bit upset by your suggestion that the breeding of dogs has nothing to do with evolution? If we have to argue over the contents of citations in the same way as the contents of the articles, we'll never get anywhere. (And I was not the person who introduced the Luskin quote to the article in the first place. Had I noticed it came from rather than I would probably have deleted it anyway.) Chris55 (talk) 09:42, 11 March 2013 (UTC)
  • Perhaps useful: some useful desriptions, including "The word evolution has a variety of meanings. The fact that all organisms are linked via descent to a common ancestor is often called evolution. The theory of how the first living organisms appeared is often called evolution. This should be called abiogenesis. And frequently, people use the word evolution when they really mean natural selection -- one of the many mechanisms of evolution." It also notes that morphological change can occur without evolution, and evolution is not progressive. . dave souza, talk 23:20, 10 March 2013 (UTC)

E as T&F "in the literature"[edit]

Despite all the careful discussion preceding it, I still feel uncomfortable with the section Evolution as theory and fact in the literature, because it seems to me that at least some of the quotations arguing one or another viewpoint are not so much addressing the nature of evolution itself, or any meaning of the word evolution, so much as these are quibbles about definitions of the terms fact, and especially, theory.

This seems especially clear in the quotation from Richard Dawkins. I think what Dawkins is really saying, in something of a pique of impatience, is, people do not understand the word "theory" in its scientific sense, and it has been deliberately misapplied in its colloquial sense to attack the concept of evolution. So let's throw in the towel, abandon "theory" as a descriptor, and fall back on "fact" as a term that is much harder for evolution deniers to twist out of shape and confuse the public. No one is going to argue that evolution is "only a fact".

I don't doubt that there are real and substantive, as opposed to merely definitional, disagreements about whether evolution is better described and understood as theory or fact. But I'm concerned that these brief quotations taken out of their original context give the illusion of substantive disagreement where there may be little or none. Milkunderwood (talk) 01:42, 24 September 2013 (UTC)