Talk:Occam's razor/Archive 1

I'm putting this expansion request for the "justifications" section here because currently, what it says is "people used to think it was metaphysically sound, turns out it's actually not, but it IS epistemologically and probabilistically sound, and as for why, er, go read a book." --AceMyth 03:15, August 30, 2005 (UTC)

I made no changes, but I wanted to note that I'm uncomfortable with the statement that "Put into everyday language, it says The simplest explanation is the best." That's not what it says; it would be more accurate to say that it says that the explanation with the fewest assumptions is best, which is not the same thing. Indeed, one of the ways to "simplify" an explanation is to make more assumptions. Admittedly, the example used of the tree refers to fewer assumptions, but the confusion of "simplest" with "fewest assumptions" has caused no end of confusion on this and I think should be avoided here.

I changed the storm/tree argument simply because the simplest explanation following the storm is NOT lightning, but a wind, and most trees felled in storms are knocked over by wind, NOT lightning. --[[user:jaknouse]

The tree is charred, not merely felled. It's burnt, in other words; wind cannot burn.

In any case an explanation that includes aliens may account for the tree but it predicts a great deal more than an explanation of the tree using just the wind. As such it is not the case that both explanations make identical predictions. Which version of Ockham's applies in this case? --[user:GKochanowsky]

Historical instances of use
Occam's Razor is arguably most profound in the context of the philosophy of science. If it is possible, then, it would be nice to collect actual historical instances of scientists trying to decide one way or another on a matter through something like Occam's razor. I think that, in practice, good examples would be hard to find; sets of theories where each is equivalent to all the others except for one being "simplest" are, I assume, hard to find.

The obvious example that pops to mind is the heliocentric theory of the solar system vs the Earth-centric system. However, I don't currently know enough about all the players to do anything like an accurate job of this.

If this were the only example that could be furnished, however, that would suggest that Occam's Razor is not really a factor in guiding science.

--Ryguasu


 * But, but, but... Earth-centric versus helicentric is the total poster-boy example against Occam's razor. At least I have it on good authority that to start with, heliocentric was much hairier, and won out not because it was simpler, but because it could "hunt" better. --Cimon Avaro on a pogo stick 10:14 27 Jun 2003 (UTC)
 * Depends a lot on what one calls "simpler". It's said that there were more epicycles in the Copernican version (a claim I've never seen worked out specifically). But the major visible motions of the planets form an incredibly complex pretzel in the sky (Kepler's metaphor), which actually is their motion in a heliocentric system (or Tycho's), while the major motions are quite simple in heliocentrism; some fine adjustments are needed in each case. Hence it can be considered a questionable application of O's R. Dandrake 04:46, Jan 21, 2004 (UTC)

Maximum likelihood principle
Having a PhD in statistics, I couldn't begin to tell you what the "maximum likelihood principle" is, although all statisticians know the method of maximum likelihood. There is no article on "maximum likelihood principle", but only a redirect to "maximum likelihood". I am aware of various papers in scholarly journals deriving versions of Occam's razor from probability theory and applying it in statistical inference, and also of various criteria for penalizing complexity in statistical inference, but I would if someone could explain what "maximum likelihood principle" has to do with Occam's razor? -- Mike Hardy


 * I would guess that it was a link from someone who doesn't understand statistics as well as you do. Would you be able to clean up that section so that it accurately reflects the link (if any) between Ockham's Razor and statistics? --Dante Alighieri 22:57 Dec 6, 2002 (UTC)

Article naming issue
I'm going to move this article to Ockham's Razor. That seems more appropriate given the man's name... --Dante Alighieri 00:31 Dec 6, 2002 (UTC)


 * It's better known as Occam's Razor. Just do a redirect from the alternate. --Uncle Ed


 * But if Occam's Razor redirects to Ockham's Razor, what's the harm? --Dante Alighieri 00:36 Dec 6, 2002 (UTC)


 * Keep in mind the Principle of Least Astonishment, which itself is akin to Occam's razor. Anyway, I made the opposite redirect: here, click on Ockham's Razor and see :-) --Uncle Ed


 * I wouldn't say it's better known as Occam's razor. Occam's Razor seems to programmers to be the right way, but to medievalists it's Ockham's Razor. And Ockham was his name and the place where he came from. So... --User:Nferrier


 * Neither his name nor the place where he came from have anything to do with it. We're talking about the article title, which is important for how readers will find the article. Think about Google and how it indexes things.


 * Remember, we're not trying to enforce a particular style on readers. We're just trying to help them get accurate info, quickly. Note that I've revised the article so that both variants are given in the first sentence. --Uncle Ed


 * Sure. But Occam's razor is wrong because, although most programmers use it, most people talking about Ockham are not programmers but medievalist scholars. They talk about Ockham's razor, not Occam's razor.


 * But I didn't start this and have no intention of worrying about what the article is called (I don't imagine there are many medieval scholars examining articles about William of Ockham and his razor here and if there are then they can change it).  -- User:Nferrier


 * Allright, that's it!! I'm writing a bot that will go and change all instances of Occam to Ockham all over the entire WORLD!! HAHAHAHA!!! All will perish in flames!!!! Or... maybe not. --Dante Alighieri 00:55 Dec 6, 2002 (UTC)

Well, Ed, are you going to change all the Ockham's to Occam's? Why do I forsee this ending up in Edit Wars? ;) --Dante Alighieri 00:43 Dec 6, 2002 (UTC)

No silly. Occam's Razor is called Occam's Razor. This is the title that most people will be searching for and linking to since this is the majority spelling. Just search Google. The fact that this spelling isn't the same as the William's last name is a historical curiosity and nothing else. --Dan


 * I hate to continue this thread but... what you're doing is perpetuating the computer related bias of the net. Because Google returns a lot of results for "Occam" does not mean that's the majority spelling, just that it's the majority spelling on the net. It is the majority spelling on the net because of programmers and other scientists. There aren't a whole lot of wired medievalists. Not sure why not.  -- User:Nferrier


 * And our audience is who? Yikes! Netcitizens. --Dan


 * And we are supposed to cater to an audience why? So much for credibility... --Dante Alighieri 01:21 Dec 6, 2002 (UTC)


 * ? What are we doing this for if there is no audience? Choosing what most English speakers use is the most useful thing to do since it exposes us to the widest possible audience. This is also a naming convention. --Dan


 * Entitling an article a certain way does not perpetuate bias. It's purely a matter of serving the public. Please note that the first 3 words of the first sentence in the article clearly show that Occam's and Ockham's are both used. Would you like to add a usage note to the article? --Uncle Ed

I strongly support the Ockham spelling. This is the one used by most encyclopedias, as it is clearly the correct one (see http://www.seeatown.com/search/ for a quick meta-search). Occam is the latinized version and there's really no good reason to use it. Most importantly, spelling throughout the article should be consistent, which it currently is not. --Eloquence


 * The only reason to use Occam's Razor as the article title would be if it were more easily found by our readers. Personally, I think this is not a very important issue. I'm more concerned with philosophical issues raised by the article. For example, if a man speaks in a forest and there is no woman around to hear what he says, is he still wrong? (see feminism) --Uncle Ed


 * I'm with Eloquence here. If Wikipedia wants to be a serious encyclopedia then we should put it under the name that the involved experts and scientists think it should have. For linking things under alternative or popular names we have redirects, and Google is also not much of a problem as long as the word "Occam" appears somewhere on the page. -- Jan Hidders 17:46 Dec 6, 2002 (UTC)

I have to agree with Ed here. The most useful thing for us to do for our readers and contributors is to use what they are most likely to naturally search for or link to. Google isn't perfect but it does show that there are 50% more webpages that use the "Occam" spelling vs the older "Ockham" spelling. And part of what we are doing here is to make our encyclopedia more accessible to the general public than regular encyclopedias have been (and continue to be). There is also the 'use common names of persons and things' naming convention that should be followed. --mav


 * We do not lose accessibility by redirecting to Ockham's Razor. The main reason not to do so in cases of native spellings vs. anglicized ones is the potential for confusion: If I search for Munich, I don't expect München, so that may result in confusion. Many of the "Occam" pages you will find over Google look like the current article: They call it "Occam's Razor" but also refer to William of Ockham. This is, in my opinion, a case where the average reader would prefer consistency and some background information on the different variants of the name. The current variant is the confusing one.


 * In any case, we need to come to a resolution here. Should we vote? Currently I'm counting four people supporting a move and three against. --Eloquence 19:19 Dec 6, 2002 (UTC)


 * Not when one form is clearly more widely used than another. "Occam's Razor" -"Ockham's Razor" still yields 27,300 results vs "Ockham's Razor" -"Occam's Razor" 19,100. So the naming convention has us use "Occam". --mav


 * Mav is right, the naming convention dictates Occam, however unscholarly and confusing it is. But as far as I can tell the arguments for this convention are simply spurious. If we move the page then (1) ease of linking does not change because of redirects, (2) you will still find the page with Wikipedia's own search engine if you search on "Occam razor" (just like you find it now with "Ockham razor") and (3) Google will still rate the page just as high and show it in the top of the search results if you look for "occam razor". So I don't see why we should compromise here the quality of Wikipedia as a work of reference. However, I don't have the time to go and debate this extensively on wikipedia-l. -- Jan Hidders 21:48 Dec 6, 2002 (UTC)

Ditto in reverse. The Ockham title redirects here already. What you missed was the ranking of our articles by external search engines: Since most people will be searching for the Occam spelling then we should do all that we can to make sure they find our article on the subject. That is one reason why the Occam spelling should be the title of the page (sic. H1 title). --mav


 * As far as I can see that is the only reason that comes close to making a little sense. However, Google is the main external search engine we should worry about and I don't know much about other search engines but for Google's rating it doesn't matter very much if the word is in < H1 > or not because Google puts much more emphasis on the linking structure. So what other arguments are there? Besides, getting as much people to find us should not be our highest priority, that should be building a high-quality encyclopedia. If we can achieve that then the people will find us anyway and with that priority you have a better chance of motivating experts to stay and write in Wikipedia. -- Jan Hidders 23:31 Dec 6, 2002 (UTC)


 * Look, I'm sorry if it's slightly more common to use Occam than Ockham. Many people don't know how to spell words like jeopardy, February, and Wednesday. Should our articles reflect that? Our current president seems to enjoy pronouncing "nuclear" as "nukyalur"... let's please not move that article to his version. :) Yes, I realize that I'm using hyperbole here, but my POINT is that I feel that it should be the responsibility of this encyclopedia, when there are two variant spellings, to support the most correct one. This is not to say we exclude the other, but that it merely redirect to the correct one. Now, we can get into a discussion about whether Ockham is truly more correct than Occam, but that's my 2¢. --Dante Alighieri 22:17 Dec 6, 2002 (UTC)


 * Correct usage in English is the form most often used by English speakers (there is no centralized committee deciding these things). If we stray from that concept too far then we enter into the realm of competing ideas on just what is most correct. And for terms ported into English form non-Latin-1 languages this opens up a can of worms. Granted this particular case isn't as clear cut as many others are but there still is a majority usage at hand; Occam. The fact of the matter is that Ockham's Razor has been used by English speakers for so long that the spelling has mutated to be more pronouncable and easier to spell by English speakers. Thus we have "Occam's Razor". The guy's name hasn't been used by English speakers to any comparable extent so it has not been Anglicized. This is part of the evolution of English. --mav

Right. We are not a style guide or usage guide. Our mission is only to report, not to prescribe! Sorry for shouting, but I thought you'd hear me better if I raised my voice ;-)

For example, there is my beloved word hacker. All who are truly informed and righteous know that the REAL MEANING of hacker is a person who enjoys extending the capabilities of computer systems. Thus, Linus Torvalds is a hacker. Those nasty, money-grubbing folks in the news media 'persist in using the innocent term hacker'' to mean "someone who breaks into computer systems or cracks copy-protection". They are wrong, WRONG, WRONG!!!

We should enforce the correct meaning, right?

No.

It is our sad yet earnest duty to use the word the way it's most commonly used.

And now I climb down from my soapbox and rest a while, hoping my blood pressure returns to normal. I will go outside and look at butterflies and flower blossoms....

--Uncle Ed


 * I couldn't disagree more. An encyclopedia is a work of reference and therefore prescribes by definition. You cannot write a good encyclopedia without paying attention to whether your use of language is precise and correct. If you use in an encyclopedia the word "hacker" you have to make sure you use it in a correct way. -- Jan Hidders 23:31 Dec 6, 2002 (UTC)


 * So no one minds if the entire article uses the spelling Ockham but it's titled Occam?!?! --Dante Alighieri 22:48 Dec 6, 2002 (UTC)


 * Indeed. That's probably the strongest argument against putting articles under the "common usage" title instead of the "more correct" title. It forces you more or less to use the common usage name in the article itself where you normally would use the more correct name. That's very annoying, especially for people who actually know a thing or two about the subject and would like to contribute. -- Jan Hidders 23:31 Dec 6, 2002 (UTC)


 * See my comment below. --mav


 * That's fine with me since that is a style issue and not a naming convention issue. You should state in the first line that the most widely used spelling is "Occam" but that academics prefer to use Ockham. This is how I treat pseudonyms (See Linda Lovelace and Billy the Kid) --mav


 * Well, if you're gonna keep pestering me about it, then I guess I better change the spelling. Done. --Uncle Ed


 * Nooooo!!! My beautiful plan to change the spelling to Ockham... ruined! *sob* ;) --Dante Alighieri 22:55 Dec 6, 2002 (UTC)


 * You're funny and good-natured. It's been a pleasure making your acquaintance. And now I must go off-line for the weekend. Bye! --Uncle Ed

Sorry, but the course of action here is simply not logical. Naming conventions are just that, conventions, they should not be treated as dogma, especially in border cases. The current variant with interchanging spelling is the more confusing one, and that's the problem. The Google check is not very helpful either, as the difference is marginal. Also, the claim that Occam is an americanized version is incorrect, it has been used earlier (since Latin has no "k") and is apparently now increasingly being corrected.

The article should be at Ockham's Razor. So far this is the option that most people support. I say we move it. --Eloquence 00:04 Dec 7, 2002 (UTC)


 * The world is not a logical place and trying to make it conform to logic is not our role here. As Ed said, we are here to report, not prescribe. The usage of "Occam's Ravor" has diverged from the spelling of William's last name as part of the evolution of our language. BTW, 50% greater is more than a "marginal" difference. --mav


 * Marginal in the sense that the correct form is sufficiently wide-spread to use it here. Note that the town of Ockham, Surrey still exists in England. See what I wrote above about the etymology -- it's the other way around. Sorry, but in the absence of consensus, we'll have no way to make a decision except by voting. If the opinions haven't shifted by tomorrow, I'll move the article. --Eloquence


 * Haven't you heard that VottingIsEvil? ;) Besides you can't vote away a naming convention. Unless there is a clear consensus to change a convention then it isn't changed. There isn't a clear consensus to move this article so it shouldn't be moved. There is no reason not to use the academically correct spelling throughout the article in the same way as Boreman is used throughout the Linda Lovelace article or Bonney is used throughout the Billy the Kid article. That is a style issue. Naming conventions are designed so that the largest number of people can find the article and link to it easily. --mav


 * 1) Need I point you to my reply, VotingIsGood? 2) We're not voting it away, we are interpreting it differently. 3) That's illogical, because that means a particular POV is retained, which is also not supported by consensus. "Being first" does not equate "being right" and I hope we never seriously consider such a policy. 4) We already discussed the finding issue. That's not a problem.


 * Sure, it's not a big issue, and I can certainly sleep with Occam's Razor if the balance changes. I'm primarily interested in making sure that our conventions are not interpreted dogmatically where it makes absolutely no sense to do so. In the absence of a good decision making process, written conventions can quickly become scripture. The anti-anglicization people had a few good arguments, and they are especially applicable in cases like this one (which is not even about anglicization, but about latinization of an English word!).--Eloquence

This one is not a big issue for me. Clearly both forms are commonly used. A more appropriate rule for this situation might lie in an extension of the American/British English rule: When there are two commonly used English forms prefer that used by the person starting the article. That being said put my vote down as somewhat in favour of keeping the article where it is. Eclecticology 00:53 Dec 7, 2002 (UTC)

Can we compromise on leaving the article at Occam for Google ranking reasons, pointing out in the first paragraph that Ockham is correct, and using Ockham throughout? AxelBoldt 03:06 Dec 7, 2002 (UTC)

Note to Axel: Mathematicians consistently spell it "Occam's Razor". I am a PhD Mathematician and have never seen it spelled any other way in the literature. It is definitely NOT NPOV to assert that one spelling is "correct"; one reflects the geographic origin of the philosopher, but the other reflects long-established usage, including usage in the sciences (naturally enough, excluding history). --User:LenBudney


 * I didn't assert that the Ockham spelling is correct; I asserted that historians and philosophers consider it to be correct, which is the truth. Second, mathematicians count among the laypersons in this debate, and the laypersons are already mentioned. The concept has no particular connection to mathematics. AxelBoldt 05:03 Dec 10, 2002 (UTC)


 * I just saw your change comments, and beg to differ: Mathematicians are certainly NOT laymen in this discussion. They (and other hard scientists) are among the prime users of Occam's Razor; they are AT LEAST as relevant to the discussion as the historians and philosophers are. --User:LenBudney


 * I have to agree with Axel here. There really is no reason to mention mathematicians specifically. You might as well also state the preferred spelling by Fundamentalist Christians, who also are familar with the term because it is thrown in their faces so often. --mav


 * I changed it to "scientists", lumping together the principal users of Occam's Razor. At issue here is that experts of historical bent spell it "Okham", but "Occam" is not merely a layman's error: experts who use the principal and consider it foundational to their vocations also spell it "Occam".


 * I for one am happy with that. --mav


 * I can live with that, even though I think it wouldn't affect Google ranking that much and I still feel that we should worry more about being correct and less about our ranking in external search engines. -- Jan Hidders 14:36 Dec 7, 2002 (UTC)


 * I've already suggested exactly the same thing above. And Jan, what might be corrcect for historians and philosophers in this case isn't the same thing that is correct for mathematicians and also the majority of our readers who don't fall into any to those categories. --mav


 * We are all historians and philosophers. :-) What the majority of readers think is correct is IMO irrelevant. If the majority thinks that creationism is science are we then going to report it as such? Of course not. An encyclopedia is supposed to reflect the current standing in academic thinking. So if the relevant scientists say that Ockham's razor is the most correct form then that is were we should put it. Anyway, the article stays where it is, the discussion is closed, I have better things to do, so you may have the last word. :-) -- Jan Hidders 21:27 Dec 7, 2002 (UTC)


 * I agree that what the majority thinks is often not correct and that we should always try to report the current academic understanding. I would add that our NPOV policy states that we should also report on how large groups of people interpret and express the things we describe. But it is still very important for us to try to anticipate what readers will be searching for and linking to - thus our preference for common names for page titles. By all means we should have the more technically correct names in the articles themselves and (where appropriate) have those terms redirected to the common titles. So the nature of the Internet, our method of interlinking articles and the fact that mostly non-expert volunteers are contributing are the main reasons why we do things a bit differently than dead-tree encyclopedias. --mav

I think the logical support for the current compromise is rather weak, for the reasons I already gave above, but I can live with it. --Eloquence


 * My two cents here. I don't understand why we are too concerned about Google ranking. Let us maintain accuracy and through the innumerable clones or mirror sites of Wikipedia, let the accurate usage propagate. We won't lose anything by not being ranked #1 for a particular query. -- Sundar 08:51, Jan 6, 2005 (UTC)

After all the debate about the name (largely irrelevant to the quality of the article) I think we should congratulate ourselves that this article is now well written and comprehensive.

And btw Ockham is a lovely little place. Do give it a visit if you're ever passing through England. -- User:Nferrier

FWIW, I'm pretty sure that the reason there's more than one spelling is because English was mostly spelled phonetically back then. There really was lots of spellings of the name of the village of Ockham/Occam. William of course came from there. The problem comes about because the spelling of the village and some of the spellings of the rule turned out to standardise differently by sheer bad luck.

So both are technically correct.

Atleast, that's my theory it sounds plausible, and I'm sticking to it.WolfKeeper

Reference to demons in Greek belief
Moving this example out:


 * Similarly, ancient Greeks would probably consider demons to be a much simpler explanation of disease transmission than germs, which were barely understood even in the 19th century (see also Ignaz Semmelweis).

Reasons:
 * We do not really have 90% of ancient Greek writings, so any assumption about ancient Greek beliefs is shaky at best. Democritus posited atoms as the building blocks of matter, for example, but most his writings did not survive the Dark Ages. Many early ancient writings and beliefs strike us as distinctly modern. We do know that later Christians believed in demons as the origins of all diseases for centuries, and punished those who didn't, but this leads us too far into POV vs. NPOV territory.
 * It's not really a good argument anyway, because the lack of simplicity of the demon hypothesis is fairly obvious (requires: definition of demons, explanation of lack of observation, interaction between demon matter and physical matter, assumptions of demon motives etc. etc. etc. ......). To make such an argument plausibly would require reference to an ancient writing which weighs the demon hypothesis against other arguments and considers it to be simpler. More likely, Occam's Razor wasn't applied at all by the demon-lovers.

Perhaps a short reference to the debate about Semmelweis' findings would be better, as here we have two hypotheses (the balance of juices vs. invisible germs), the simplicity of which was not immediately quantifiable.

I'm also not too happy with the creation vs. evolution example. Evolution requires hardly more assumptions than "scientific" creationism, especially as the more "scientific" creationists acknowledge that evolution takes place on a microbiological level, or in computer simulations -- these variants require almost all of the assumptions of evolution, and then a huge body of assumptions about an intelligent designer. The more biblical variants require more assumptions about the designer, and less about evolution. Therefore the argument seems to violate NPOV as currently presented. --Eloquence

References?
This Usenet post seems to contest the following Wikipedia claim:


 * Ockham himself used his principle to argue that God's existence cannot be deduced from reason alone.

Can someone add a reference for this claim, please? --Eloquence


 * After a little looking around:
 * http://skepdic.com/occam.html (4th paragraph)
 * http://www.utm.edu/research/iep/o/ockham.htm (section Reason and Authority)
 * http://atheism.about.com/library/FAQs/skepticism/blfaq_logic_occam.htm (about the 10th paragraph)
 * http://www.drury.edu/ess/philsci/Outline2.html (the part about Ockham)
 * http://www.newadvent.org/cathen/15636a.htm (2nd paragraph)
 * http://www.y2kind.com/ockhams_razor/
 * http://philosophy.fullcoll.edu/res/profiles/ockham.pdf
 * By the way, shouldn't it be pointed out that there is a strong and a weak interpretation of the razor? The strong interpretation is that the simpeler theories are more likely to be true and the weak interpretation is that it is just more practical to investigate the simpeler ones first. The former claim is, I believe, a metaphysical claim and the latter one is not and AFAIK the usual one in the common philosophy of science. -- Jan Hidders 13:15 Jan 3, 2003 (UTC)


 * It's quite clear that Ockham argued that religious beliefs could not be scientifically proven, but did he ever use the Law of Parsimony to do so?--Eloquence


 * Hmm, you are right. I reread all the links I found and only the third one seems to come close, and even there I find no explicit reference. It seems such a logical conlusion and that is exactly why we need to be be careful here. -- Jan Hidders 15:16 Jan 3, 2003 (UTC)

I got the claim about Ockham's God/rationality argument from the first reference given in the article, http://hepweb.rl.ac.uk/ppUK/PhysFAQ/occam.html. On reflection though, I wouldn't trust that source too much. Here is a quote from EB: "He used it, for instance, to dispense with relations, which he held to be nothing distinct from their foundation in things; with efficient causality, which he tended to view merely as regular succession; with motion, which is merely the reappearance of a thing in a different place; with psychological powers distinct for each mode of sense; and with the presence of ideas in the mind of the Creator, which are merely the creatures themselves." No other use by Ockham of the principle is mentioned. Ockham seems to have used the principle mostly (exclusively?) in the original sense of "get rid of superfluous entities", and not of "prefer simple theories".

The very nice essay in the Stanford Encyclopedia of Philosophy http://plato.stanford.edu/entries/ockham/ has this to say: "He certainly believed in immaterial entities such as God and angels. He did not believe in mathematical (*quantitative*) entities of any kind." and a quote from him: "For nothing ought to be posited without a reason given, unless it is self-evident (literally, known through itself) or known by experience or proved by the authority of Sacred Scripture." AxelBoldt 16:47 Jan 4, 2003 (UTC)

I removed this:


 * It can be pointed out that there is a "strong" and a "weak" interpretation of Occam's Razor. The strong interpretation is the idea that simpler theories are more likely to be true; whereas the weak interpretation suggests that it is more practical to investigate the simpler interpretation of an argument first. The former claim is a metaphysical claim, while the latter one is not ; however it is usual in the common philosophy of science.

First, this distinction appears not to be made, at least according to a cursory Net search. Second, I fail to see how the "more likely to be true" claim is metaphysical, it seems to be statistical, based on prior observations. If flying saucers were common (observation!), the flying saucer hypothesis would not be as unlikely as it is otherwise. Practicality doesn't come into the equation much - it is perfectly practical to examine many wild hypotheses, but it is nevertheless not done. --Eloquence 14:20 Jan 3, 2003 (UTC)


 * First, let me say thanks for removing the remark. If I thought it should be added then I would have done so myself. :-) Well, according to a colleague of mine who did his [Amaster's thesis on the philosophy on science the usual interpretation is the weak interpretation and he told me that the justification is the practicality argument and definitely not the statistical argument. I also don't think that is how William himself justified it (see the remark on Philosophy of science). I regret using the word "interpretation" because the two views do not differ on what the rule says (you should do the same in both cases) but on its justification. As far as metaphysics is concerned, the razor is often compared to (or said to be derived from) the Aristotelian principle of simplicity and that is usually regarded as a metaphysical principle. Also for this principle there are statistical arguments, but that doesn't mean it is no longer a metaphysical principle. Anyway, I'll see if I can find some more answers instead of question. :-) -- Jan Hidders 15:16 Jan 3, 2003 (UTC)


 * I think a distinction has to be made between the historical "Ockham's Razor" and the modern scientific principles that relate to it. --Eloquence

I think that Occam's Razor can be regarded as an approximate statement of the principles of Bayesian inference: given that in many simple independent cases posterior probability = likelihood ratio x prior probability and that most event have probabilities significantly less than 1, the more entities, the lower the posterior probability, all else being equal. -- Anon.
 * But here the "all else being equal" is a classic example of the overwhelming exception. -- Cimon Avaro on a pogo stick 10:10 27 Jun 2003 (UTC)

See also this interesting link: http://rii.ricoh.com/~stork/OccamWorkshop.html -- Anon.

Naming again?
Should this be at upper case (Occam's Razor) or lower case (Occam's razor) ? Martin


 * On Wikipedia talk:Naming conventions (capitalization) lower case has been suggested. I'll make the change if nobody objects... Martin


 * Objection. Common form is capitalized. Most pages that link to it use the capitalized form as well. Redirect is already in place. --Eloquence 18:14 May 4, 2003 (UTC)

Cutting in: I think it should be Ockham's -- no reason why Occam's cant redirect to the proper name and to correct a seven hundred or some-ought years of misuse and misspelling--be it Latin mispelling or not. - &#25140;&#30505sv

Both are correct. Occam's/Ockham's razor predates the earliest dictionaries, by several hundred years... there simply wasn't any standard for Ockham's name, English was largely phonetic. Wolfkeeper 19:10, 27 Mar 2005 (UTC)

Ockham's Razor - storm/tree
Nobody loves a smart arse but may I say that the storm could have been caused by the fall of the mighty tree. That's a very simple explanation, much more believable than the notion that a storm can be caused by the flap of a butterfly's wings.

Ken

http://www.tauroscatology.com

Galileo reference
Might anyone have the precise reference for Galileo's satire of hyperOccamism? I know it's in the Dialogue, but that's a big book. Dandrake 04:40, Jan 21, 2004 (UTC)

Occam's Razor versus the law of parsimony
Currently, the article is factually incorrect in that it equates Occam's Razor with the law of parsimony. See the Physics FAQ entry. -- Dissident 21:52, 18 Mar 2004 (UTC)


 * The article doesn't do that. It does state that people often do use the two interchangeably however. --Dante Alighieri | Talk 01:26, Apr 2, 2004 (UTC)

Lower- and upper-case
Why is the "R" capitalized? We don't do that with things like Maxwell's theorem or Zorn's lemma or Gauss' law or the Gibbs phenomenon. I just changed a bunch of incorrectly capitalized letters to lower-case, and I wonder if the same should be done with "Razor" on the grounds that the page was written largely by people not familiar with that aspect of Wikipedia's style manual. Michael Hardy 00:00, 10 Jun 2004 (UTC)

"Occam's Sword"
I removed the references to "Occam's Sword". A Google search revealed that nearly all references were from this very article republished in various places across the web, except for Occamssword.com. My conclusion is that the Occam's Sword references were added to the article by the author of the page, who created the "Sword" himself. The content is therefore un-encyclopedaic. &mdash; Adam Conover &dagger; 22:22, Jun 10, 2004 (UTC)


 * The same user has now gone and added a big section on Occam's Sword over at Eliminative materialism. It's not exactly my area of expertise, how does it look to you? Bryan 00:42, 13 Jun 2004 (UTC)


 * Since Occamssword.com is the only place in which Occam's Sword is mentioned, the only conclusion is that this is a case of a fringe theorist inserting his own opinions into articles. Additionally, it's patent nonsense. Our policy should be to delete it whereever it appears.   &mdash;  Adam Conover &dagger; 01:13, Jun 13, 2004 (UTC)


 * Okay. I reviewed his other edits and didn't find any other significant additions, just a few cross-links between articles that seemed reasonable to me. I'll keep an eye out for his additions in the future and request that he discuss them here. Bryan 01:19, 13 Jun 2004 (UTC)

Hello Bryan and Adam. If I was overzealous in promoting my theory (Occam's Sword) then I apolagize. I mean/meant no harm. I have made other positive contributions to the Occam's razor entry including: an entry in the Science and Occam's razor section, the Biology and Occam's razor section, the history of Occam's razor section, and the Chatton's anti-razor and Occam's razor section among others. Perhaps if I were to make a more objective presentation of my theory as an enrty for Occam's Sword and then link it to Occam's Razor you would find it more acceptable. Again I'm sorry for any perceived harm I may have caused. Phil O. Cetes


 * No, it's alright; you came in here to talk: to discuss the issue under dispute, which is the right way to deal with these sorts of uncertainties. I myself am not familiar with the details of these philosophical issues, all I had to go on was what was written here. Anyway, that said, there may be problems with including mention of Occam's Sword here if, as Adam suggests, your page is the origin and main source for the term; see No original research. Wikipedia's supposed to report on information that is already "out there" as part of the general body of human knowledge, not propose brand new ideas itself. This isn't intended to impugn your theory; every theory tends to start out with just one person proposing it, after all. But it may not be suitable for a general encyclopedia until after knowledge of it has become more widespread (even if not "generally accepted"). Do you know of any other references to it that Google has missed? Bryan 02:38, 13 Jun 2004 (UTC)

Bryan, I should have read the policies for wikipedia before posting anything. I regret not having done so. I did not realize new ideas could not be included. unfortunately for me there is no other source for Occam's sword other than occamssword.com. The site occamssword.com includes an extensive bibliography and subject guide for occam's razor. Perhaps it would be alright to include a link in the external links section of Occam's Razor so that people would have access to it? What do you think? Phil


 * There's so much Wikipedia policy lying around that even I, who have been here practically from day one, still occasionally run into situations where I break a guideline I didn't know existed. It's no big deal, though; we're pretty informal around here. :) That bibliography over on your site looks very extensive, I wouldn't object to linking there for that purpose. Perhaps something like An extensive bibliography of Occam's Razor-related publications? (oh, and just in case you hadn't seen it, at the bottom of the "no original research" page there's a couple of links to wikis that do accept original research were you might port over the text on Occam's Sword that you originally posted here). Bryan 19:16, 13 Jun 2004 (UTC)


 * Phil -- first of all, let me apologize for my harsh tone. There are a lot of unreasonable anonymous posters who force their opinions into articles over and over, and I mistook you for one of these scurrilous sorts. It is commenable that you came here to apologize and discuss the matter -- don't worry, there are no hard feelings, and no one will blame you for not being aware of wikipedia policy. As for what place your site has in this entry, I suggest adding this link to the article: An extensive bibliography of publications related to Occam's Razor. Unfortunately, I think that linking to Occamssword.com itself (i.e., Occam's Sword, a new formulation of Occam's Razor] or somesuch) is still to much of original research to be appropriate for the article. Your bibliography is definitely a useful resource, however. Additionally, I'm with Bryan in encouraging you to post your work to a Wiki which encourages original research.   &mdash;  Adam Conover &dagger; 00:57, Jun 14, 2004 (UTC)

Adam Thank you for your apology. No offense taken. And thank you for the recommendation for the link. I'll go ahead and add it. Thank you both for the encouragement to post at wikinfo. Would it be permissable to create a link from the occam's razor entry at wikipedia to the occam's razor entry at wikinfo? Also if its not too much trouble could one of you update the wikinfo entry for occam's razar so that it matches the one in wikipedia? It would save me from having to retype it. take care, Phil. 00:37, Jun 14, 2004 (CT)


 * I've never been to Wikinfo before, and taking a look at it now I see that I'd need to create an account and log in in order to edit there. However, since it's a fork of Wikipedia, it's under the GFDL too; you can just copy and paste as much of Wikipedia's Occam's Razor article over there as you like. I suspect the markup code will be basically the same, no need for retyping. Bryan 05:42, 14 Jun 2004 (UTC)

Bryan and Adam, I hope you do not mind, but I put a link from occam's razor at wikipedia to the same entry at wikinfo. I read that wikipedia encourages links with sister sites. If its not ok let me know. Thanx Phil. 17:10, 17 Jun 2004 (CT)

I have put Phil's original work, which is indeed welcome on Wikinfo, in a separate article, Occam's sword and substituted that link in this article. It is only a stub now, but hopefully Phil will soon substantially improve it. Fred Bauder 11:46, Jun 23, 2004 (UTC)

Thank You Fred, Phil 1:14, JUN 25, 2004 (CT)

The example with musk oxe
Citation " Williams provides an example from zoology. Musk oxen when threatened by wolves will form a circle with the males on the outside and the females and young on the inside. Biologists often cite this as an example of altruistic behavior by the males that is disadvantageous to them individually but beneficial to the group as a whole and thus supportive of the group selection theory. Williams, however, offers an alternative interpretation based on individual selection. When treatened by a larger or more dangerous animal, an individual Musk oxen will either fight of flee. The males being larger than the females and young perceive wolves as less dangerous and are willing to fight while the females and young flee to the interior of the circle. From this perspective there is no need for group selection. Each individual is acting in it's own self interest."

I think that most biologists will disagree with that explanetion. It is not even the simplest and most basic (now that we are talking Occam's Razor). You see, the way evolution works is, that the genes that are propogated in most copies will end up determening the development of that particular species. If the male musk oxe runs off, leaving his offspring to the wolves, his genes will not be propogated. If however he takes up the fight his gens will live on in his offspring. And thus the "stay-and-fight" gene prevails. An understanding of the underlaying fact, that evolution act's on genes not individuals or groups solves the puzzle. You may want to change the example about musk oxe.

Jens Olsen (sorry about my English - I'm Danish)

The musk oxe example continued...
Actually what I describe is called kin selection, and it just accured to me to look it up in wkikipedia, and ofcause there was an article on the subject.

Jens Olsen

Why "razor"?
When I first heard of it, it sounded as though someone had designed a razor (literally) on the principle of simplicity.

I've checked OneLook, and none of them seem to give an etymology for the "razor" bit. One explanation I've heard is that it's a metaphor referring to a 'sharp' divide between the simple and the complex. Though I'm not sure that makes sense. Or maybe it's a razor that shaves away the unnecessary complexities.

Does anyone have an idea? -- Smjg 16:39, 5 Oct 2004 (UTC)


 * I don't have the direct answer on who and when coined the term "razor". I seem to recall reading it was not Occam, that it was a later terminology applied to the idea. Looking at the Oxford English Dictionary it shows the first recorded entry for "Occam's razor" as 1856, however I am fairly confident it was used before then. Why is it called "razor"? This should probably be in the first paragraph of the article, but it is really very simple. Razors cut things. From another quote in the OED: "There is a direct appeal to Occam's Razor: we should not acknowledge two or more irreducibly different types of entity if we can get by with fewer." .. ie. if there are two explanations for the same thing, we should cut one out and leave the most simple. Stbalbach 04:06, 7 Oct 2004 (UTC)


 * From the misty fogs of first year metaphysics, I seem to recall that a standard example of a non-existent object is Plato's beard (Plato was clean-shaven, but Plato's beard must exist in some sense in order for Plato to not have it). The lecturer for that course implied that it was Occam's razor because it gets rid of Plato's beard. I have no idea if this is why it's a razor, and to be honest it sounds suspicious, but I like it anyway. :) 212.9.22.230 15:27, 4 August 2005 (UTC)

This is a great question and I was about to ask the same. That means I don't know the answer, heck, I just came here to check what it was about. So I'd be grateful that if you know the answer, please include it in the article. Or maybe even speculate the options if there is no known answer. Thanks. --62.78.195.223 17:06, 18 November 2005 (UTC)

I'm assuming that it comes from the one offered translation that says: "Shave off" (do not introduce) unnecessary entities in explanations. I have no expertise here, but that seems like the most logical conclusion. 68.100.115.135 14:52, 12 March 2006 (UTC)KevinPuj

POV?
"Occam's Razor could also be said to apply to the elimination of the soul as a superfluous entity."

This being a standalone statement with no citations of reference for who said it, and not backed by further philosophical discourse or explanation as are the other assertions in the article, this seems to me fairly POV. Or at the least unsupported. But I'm new here. Any thoughts? - alavery7 17:00, 29 Nov 2004 (UTC)

This refers to a soul which has no observable effect (as many maintain) and it is indeed a consequence of occam's razor. On the other hand if the word were used to mean the emotional part of the mind then occam's razor certainly wouldn't apply. Barnaby dawson

"In addition there is the question of whether Creationism actually accounts for the physical evidence; the fossil record and evidence of the age of the Earth and solar system appear to falsify the story of divine creation (as described in the book of Genesis)."

This is by no means universally accepted, in fact it is currently undergoing a lot of debate. As such is it POV, and has been removed pending further discussion.

Invitation
Work is currently in progress on a page entitled Views of Creationists and mainstream scientists compared. Also currently being worked upon is NPOV (Comparison of views in science) giving guidelines for this type of page. It is meant to be a set of guidelines for NPOV in this setting. People knowledgable in many areas of science and the philosophy of science are greatly needed here. And all are needed to ensure the guidelines correctly represent NPOV in this setting. :) Barnaby dawson 21:29, 27 Dec 2004 (UTC)

name change - revert?
The change of spelling, from the most common to one of the many variants, was apparently done without discussion. Given that this spelling is not as common (a quick Google will demonstrate this) I think it should be changed back. Banno 06:02, Jan 6, 2005 (UTC)


 * I agree, most common name is best as the main title. Bryan 07:32, 6 Jan 2005 (UTC)

Did you mean without consensus when you said without discussion? See, a newly sectioned portion. -- Sundar 08:52, Jan 6, 2005 (UTC)


 * Y'know, it's probably a good idea to leave it in one spot for a really long time, and let whomever and whatever adapt to the fact that wikipedia redirects. I guess I'm posting this here for ppl who somehow miss the entirely too huge of a discussion about which name this should fall under. --sp00n17 03:13, Jan 8, 2005 (UTC)

Article moved back to most common spelling. --mav 03:05, 22 Jan 2005 (UTC)


 * You do mean blatantly and obviously incorrect spelling, right mav? --Dante Alighieri | Talk 17:56, Apr 13, 2005 (UTC)

I think the name should be changed to Ockham's Razors. It is not as if there is only one form or that even one form is attributed to Ockham.

MediaWiki Bug?
I made two edits to this page, one sectioning it, adding my comment at two places and the next edit signing one of those which I had forgotten to sign. Now, if I see the page history, it shows only one edit (the second edit) in my name and shows the previous edits in diff! But, interestingly, the current version is the latest. Also, both the edits are missing in my contributions! Is the world real or is it just Wikiholism?


 * Oops! Everything looks normal now. The problem seems to be temporary. In the meantime, I filed a bug too. Kindly confirm my sanity :p -- Sundar 09:30, Jan 6, 2005 (UTC)

-- Sundar 09:03, Jan 6, 2005 (UTC)

Think horses, except in Africa when think zebras.
Occam's Razor does not of course PROVE that simplest is best, merely that simplest should be your first choice.

If simplest has a flaw, move on to the next simplest choice, and so on.

"When you hear hoofbeats, think horses, not zebras", works in most places, but in Africa where "think zebras, not horses" may be a better choice. Reason: zebras are native to Africa and horses are rare in Africa.

One might say "... Think horses, not zebras, except in Africa", and leave it to the reader to look up why there is an exception.

Tabletop 03:17, 22 Jan 2005 (UTC)


 * Occam's Razor doesn't prove that the simplest should be your first choice; it states it as a methodological principle. Mel Etitis ( &Mu;&epsilon;&lambda; &Epsilon;&tau;&eta;&tau;&eta;&sigmaf; ) 10:41, 4 Mar 2005 (UTC)

In fiction?
Is there any point to this? Probably every conceivable topic or person has been mentioned in fiction somewhere. Surely, such mentions should be included only if they're significant for the the article (which none of these seems to be). Mel Etitis ( &Mu;&epsilon;&lambda; &Epsilon;&tau;&eta;&tau;&eta;&sigmaf; ) 09:34, 9 Mar 2005 (UTC)


 * Can we have a few lines on how fiction writers use the razor as a literary device that helps them to explain things? e.g. God's Debris. Just as Parallel universes are used as a literary device, there may be several examples in fiction, esp., science fiction which use the razor to explainaway things. --Gurubrahma 05:39, 26 November 2005 (UTC)

latin
frustra fit per plura quod potest fieri per pauciora, I think best translates into: in vain it is done by many what can be done by few. 'Fit' is the passive third person form for 'facere'.

Occam's Toothbrush?
I've heard the term "Occam's Toothbrush" used in computer science when referring to optimisation of intra-processor instructions. Is this term really in use, or is it merely something my teacher made up? &mdash; J I P | Talk 07:52, 23 Mar 2005 (UTC)


 * Why don't you ask your teacher? -- Smjg 08:54, 22 Apr 2005 (UTC)

http://www.cs.berkeley.edu/~randy/Courses/CS252.S96/Lecture03.pdf Wolfkeeper 15:14, 2005 Apr 22 (UTC)

In Science
Am I missing something, or is the first couple of huge paragraphs in the "in science" section conflating parsimony with independent observation? The counterexamples are "undetectable beings" and "flying saucers". These examples aren't only needlessly complex, they also employ entities that cannot be observed. This conflates the issue. For exmaple, if I say that tsunami are caused by the devil, that's a simple explanation, but the examples seem to imply that it would conflict with Occam's razor. It doesn't; it conflicts with empiricism in that we can't make any provable claims regarding "the devil" or any unobservable entity/universe/etc, but it's certainly a parsimonious explanation considering that tsunami are actually understood in terms of waves through a largely incompressible fluid caused by energy released from seismic activity, which in turn is understood in terms of geology and geophysics. Maybe we can get some more reasonable counterexamples to illustrate the point more clearly? Something where we actually need Occam's razor to help us make the distinction between a preferred theory and an inferior theory?


 * I don't think examples to demonstrate Occam's razor ever work. The problem is, Occam's razor doesn't decide between true and false theories, or better or worse theories, it just states you should use the simpler one. Indeed, you should only invoke the razor if the theories are otherwise equal. 212.9.22.229 15:35, 4 August 2005 (UTC)


 * Careful here. Occam picks one theory as a working hypothesis for you. The theories don't have to be at all equal or at all equivalent.WolfKeeper


 * Ah, but your example does conflict with Occam's Razor. Materialistic explanations for the tsunami do not require us to assume the existence of a supernatural being.  Your example does, which violates the Principle of Parsimony by introducing an unneeded additional entity.  Saying "the Devil caused the tsunami" is semantically equivalent to saying "the wind blows due to the efforts of an invisible pink unicorn named Marge."

The opening paragraph
Wikipedia's Manual of Style clearly states:
 * "If the subject of the article has more than one name, each new form of the name should be in bold on its first appearance."

This is what I did, yet is was reverted. So I changed it back.

Also this is what I have to say abotu the word lampooned: All one has to think when writing something in wikipedia is: "would (or should) this exist in the Encyclopædia Britannica?" I have never seen the word 'lampooned' anywhere outside of the national lampoons, and I am a well read person. As such, it does not belong in an encyclopedia. --The Sunborn

I can kind of see where you are coming from, however the word lampooned is both historically accurate, and finds rather more widespread usage than you might suppose. For example google gives 130,000 references to it, which whilst it is not massively widespread, it is still not at all uncommon. I certainly don't agree that simply because I or anyone elses rarely meets a word that the word should be removed from a wikipedia. The word is being used entirely appropriately here. All IMHO WolfKeeper 03:27, 2005 May 4 (UTC)


 * It just doesn't seem to me that lampooned belongs in an encylopedia, I guess it could stay but I don't think it belongs. -- 16:30, 4 May 2005 (UTC)


 * I think that the fact that you've only come across it in one place fails to count as grounds for removal, but here are a couple of other occurrnces:, , , , ,.
 * As for the bolds, you reverted not only the ones in the intro (and alternative terms aren't "forms of the name"), but the ones wrongly used for book titles. Mel Etitis ( &Mu;&epsilon;&lambda; &Epsilon;&tau;&eta;&tau;&eta;&sigmaf; ) 19:59, 4 May 2005 (UTC)
 * Alright, well like I said, lampooned I guess can stay.
 * However, the "law of economy" and the "principle of parisomy" are alternative names for the article and must be bolded according to the manual of style. It is not ambiguous language, as such I will re-bold them now. --The Sunborn

Well, the article actually says that "the principle of parsimony" and "law of economy" are said to be alternative names for "methodological reductionism", of which Ockham's Razor "forms the basis". Given that Ockham's Razor is in fact much narrower in scope than either parsimony or economy, I'm inclined to think that that reading was what was meant. It may be that the summary is badly written, but I think that you need to demonstarte that before editing it in line with what it doesn't in fact say. Mel Etitis ( &Mu;&epsilon;&lambda; &Epsilon;&tau;&eta;&tau;&eta;&sigmaf; ) 22:03, 4 May 2005 (UTC)


 * You may be right. However, on page 521 of The handy science answer book it states:

"The law of parismony, also called the law of economy or Ockham's razor, proposes that a problem should be stated in its basic and simplest terms." This is a heavily researched book with 23 pages of bibliography. I assume it to be correct. -- 03:44, 5 May 2005 (UTC)


 * Er, The handy science answer book? No, that doesn't qualify as a suitable academic, authoritative source.  Nor would Science made easy, Science for dummies, etc. When I have time, I'll supply some sources of my own. Mel Etitis  ( &Mu;&epsilon;&lambda; &Epsilon;&tau;&eta;&tau;&eta;&sigmaf; ) 08:41, 5 May 2005 (UTC)

revert of new material
I've just removed ReSearcher's new material, largely because it was original research. As original research, incidentally, it needs more thought, but it still wouldn't belong here, I'm afraid (see No original research). Mel Etitis ( &Mu;&epsilon;&lambda; &Epsilon;&tau;&eta;&tau;&eta;&sigmaf; ) 08:38, 5 May 2005 (UTC)

justification and "assumptions"
From the article: "In response, philosophers turned away from metaphysical justifications for Occam's Razor to epistemological ones including inductive, pragmatic, likelihood and probabilistic justifications, which is where things stand today."

I really think that there should be more information as to exactly what those justifications ARE. This makes it seem as though there have been dozens of theories attempting to justify Occam's Razor in the non-metaphysical realm, which I doubt is truly the case, as those "inductive, pragmatic, likelihood and probabilistic" explanations are probably all reducible to "the less likely your hypothesis overall is, the more likely objective reality is to eventually screw it over".

I'm also wondering about the formulation of the principle as "making the least unnecessary assumptions". What exactly differentiates an assumption from a non-assumption? The inherent logical structure of "the earth is round" isn't any different than that of "the earth is flat", yet obviously this formulation of the razor would deem the latter an assumption and not the former.


 * Careful here. Both *are* assumptions. As far as assumptions go, they both seem to me to be roughly equivalent. Indeed the Earth is flat might be considered to be the obviously simpler explanation, then Occam's razor would chose it. However it would soon be disproved, and then an 'earth is spherical' theory would be supported. Using the razor is an iterative process.WolfKeeper


 * That's what I was trying to say: They both /are/ assumptions. Given all the data we have nowadays on the subject, I don't think that Occam's Razor would choose the "the earth is flat" theory at all. You'd have to either apply it while ignoring available data or make a theoretical application of what the razor would say back in the day when we didn't have the data we have today. Applying Occam's Razor while disregarding data that you actually have is just plain silly and can easily lead to conclusions that once you consider all the data are absurd. (Like, for example, the earth being flat :P) As for the second case, indeed we can never know whether in a particular subject we are like the people who thought the earth was flat because they didn't have the data that would show them otherwise... Which is why Occam's Razor is a heuristic and not a law.


 * What I was trying to say wasn't that "the earth is flat" isn't an assumption, it's that the risk of postulating a claim is what makes it presumptuous, and thus some assumptions can be worse than others. So even if "the earth is round" and "the earth is flat" are both assumptions, when considering the available data as a whole, "The earth is round" is less, er, assumption-y. --AceMyth 09:15, May 9, 2005 (UTC)

But that's only because the latter would require believing many things about modern science which are so ridiculously improbable as to constitute a conspiracy theory, while the former would require adopting a coherent belief set of "people don't lie without reason, the scientists have no reason to lie, the Earth revolves around itself" et cetera et cetera. Seems to me like this has less to do with the number of "assumptions" than with the quantity of what intuitively defines a statement as such, in other words, perceived risk of it being false. --AceMyth 02:10, May 8, 2005 (UTC)


 * No, there should be no such considerations. Indeed, if you can think of a theory that is simpler but risky, you should point it out.WolfKeeper


 * There are often considerations about what really constitutes simplicity though; it is often possible to phrase something so that it sounds simpler, but careful examination shows the idea to be very complex indeed.WolfKeeper


 * I think that this whole "simplicity" formulation of the razor is just misguided in the first place because nobody ever defined just what kind of simplicity we're talking about (And the dictionary definition obviously doesn't cut it, see General Relativity vs. Newtonian Mechanics). So even if there is a definition of simplicity that makes the razor valid, that doesn't help the average person running across it, who can interpret "simplicity" about a gazillion ways and is most likely to conclude that the razor says "the smarter you have to be to understand it, the less likely it is". And I've already demonstrated the problem with the "least number of assumptions" formulation, which completely ignores the holistic nature of knowledge and pretends that all assumptions are equal.


 * In the light of this, I consider rephrasing the modern, probabilistic version of the razor as something along these lines - "choose the explanation which's consistency with the whole of empirical observation relies on the set of assumptions perceived as the least improbable". Or it can even be formulated to apply beyond mere explanations of empirical observations, as "the most preferable world-view is the one which requires minimal reliance on the unknown to maintain its consistency". What do you think? --AceMyth 09:15, May 9, 2005 (UTC)

Quotations
This section has alsways bothered me. i've commented it out for the moment. First, I don't see that it adds anything useful to the article; the reader learns nothing about Ockham's Razor. Secondly, some of the quotations are not really to do with the Razor, but have a sort of superficial resemblance to some formulations of it. Thirdly, some of the others are inaccurate (e.g., the Sherlock Holmes). Fourthly, some of them are simply trivial; OK, so a fictional character mentioned Ockham's Razor &mdash; so what? Probably countless others have too. Should Metaphor include a list of quotations from novels and cartoons in which characters mentioned metaphors? Or even used metaphors? Mel Etitis ( &Mu;&epsilon;&lambda; &Epsilon;&tau;&eta;&tau;&eta;&sigmaf; ) 17:02, 6 Jun 2005 (UTC)


 * Seconded. But I think there are some useful quotations out there that we could include in the article. --AceMyth 10:33, Jun 10, 2005 (UTC)


 * There probably are, though I'd like to seem them incorporated into the text rather than added as a separate section. Mel Etitis ( &Mu;&epsilon;&lambda; &Epsilon;&tau;&eta;&tau;&eta;&sigmaf; ) 11:09, 10 Jun 2005 (UTC)

Ontology/Physics
The ontological version of Occam's Razor is not used in modern physics, simply because modern physical theories are not ontological but mathematical. A theory is prefered, not because it makes less ontological statements, but because it is computationally easier. I think this is also the case for other sciences.

The importance of the ontological version for science is overrated. Markus Schmaus 6 July 2005 14:11 (UTC)


 * I know a lot of physicists who'd disagree with you on this. You're assuming a certain philosophy of physics that's by no means universally accepted. Mel Etitis  ( &Mu;&epsilon;&lambda; &Epsilon;&tau;&eta;&tau;&eta;&sigmaf; ) 6 July 2005 16:45 (UTC)


 * What are the ontological claims of quantum mechanics? Has it more or less claims than general realtivity? Has general realtivity more or less claims than classical mechanics? Has Lagrangean mechanics more than Hamiltonian mechanics? Markus Schmaus 6 July 2005 17:03 (UTC)


 * It's always possible to find examples of pairs of theories with no ontological differences, from any period of science; the mistake is to generalise from them. There are definite ontological differences between alternative interpretations of quantum theory (do you want Everett's many worlds?), etc. Mel Etitis  ( &Mu;&epsilon;&lambda; &Epsilon;&tau;&eta;&tau;&eta;&sigmaf; ) 6 July 2005 18:14 (UTC)

I didn't pick those theories, because I think they don't have ontological differences, but because I don't know what the ontological claims of those theories are.

I don't know about Everett's many worlds, but when an apparatus measures a quantum system, the apparatus gets entangled with the system. Suppose an electron is in the state |-1/2> + |+1/2> and then the combined system of the apparatus and the electron developes from


 * 0> &otimes; (|-1/2> + |+1/2>)

to


 * (|-1/2> &otimes; |-1/2>) + (|+1/2> &otimes; |+1/2>).

Experiments, known as erasing measurements, show that those two basic states ((|-1/2> &otimes; |-1/2>) and (|+1/2> &otimes; |+1/2>)) can still interact, but outside very controlled experiments this is very unlikely.

The same thing happens if the apparatus is a human being. When a human being measures the spin of an electron the state of the world becomes a superposition of "I think spin up and the electron is spin up" and "I think spin down and the electron is spin down". In principle those two states can still interact but it is very unlikely, some physicists refer to those basic states as worlds and talk about many worlds meaning the supperposition of many basic states, which are very unlikely to interact with each other.

The Copenhagen interpretation avoids this using the collapse of the wavefunction. But its hard to interpret the erasing measurement experiments using the Copenhagen interpretation.

In most cases we do not care about the rest of the state and use the collapse of the wavefunction, because it is easier, but in some experiments, we use a "many worlds" interpretation, because it is easier.

P.S.: I just checked on wikipedia. Everet's many worlds seem to be the same. Markus Schmaus 6 July 2005 23:03 (UTC)


 * I'm not sure what you mean. If you accept the many-worlds interpretation, you commit yourself to the existence of world-branches; if you reject that interpretation, you reject the existence of those branches.  That's an ontological difference, to which Ockham's Razor is relevant.  You also mentioned other science originally; among other things, for example, biologists (in particular, but all scientists to a certain extent) are concerned with the acceptability of reductionism, as well as with the existence of species &mdash; both are ontological questions, both are subject to Ockham's Razor. --Mel Etitis  ( &Mu;&epsilon;&lambda; &Epsilon;&tau;&eta;&tau;&eta;&sigmaf; ) 18:15, 10 July 2005 (UTC)

Hey, the page currently says that Occam's Razor in everyday language is:

The simplest explanation is the best.

But then in the "In Science" section, it says

Some people have oversimplified Occam's Razor as Italic textThe simplest explanation is the best (or true) one

Not About Simplicity
"The simplest explanation is the best" is a horrible way to paraphrase Ockham's Razor.

16/64 = 1/4 by cancelling the 6s.

Ockham's Razor is not about simplicity, but necessity.


 * I agree, and fail to see how the explanation above it is not in everyday language. Though I'm afraid that removing it will start an edit war. StradivariusTV 02:27, 30 August 2005 (UTC)


 * I think the preceeding and following paras make it clear what is meant by 'simplest', and even mention this very flaw in thinking. Not an editor of this page, but I think it should stay. Nae'blis 00:04:03, 2005-08-31 (UTC)

Ockhams own writings
Just a small question: what was the original phrasing of the razor? It seems there are a great deal of references on what other people think he meant, but few as to what he actually said. Got to admit though, i couldnt be bothered to read through the entire talk page! TIA. --The Minister of War 13:52, 4 October 2005 (UTC)

It never ceases to amaze me how many people think that "Keep It Simple" needs an extra 's'. Occam's Razor seems to be totally beyond them, it is complicate-it-speak. And a truism that is not, true that is. Reading, like silence is to freedom of speech, seems to have been missed as the finer side of writing! jparranto@yahoo.com

Assume
Some time ago it was popular to have a functional definition of "assume" as "ass/u/me" meaning, if you assume something you will make an "ass out you and me." A truism isn't; true, that is. To make an assumption will definitely make an ass out of you but to make an ass out of me, you will need my consent. Occam was more oriented to the 'do not make asses by adding facts not present,' just to keep assumptions that have no merit, alive. Keep It Simple = KIS not KISS. Simple, is found after, and almost never, before. jparranto@yahoo.com

200-metre tall space aliens
I guess this part was written by a SciFi geek, and normally I'd be all for it, but considering the context wouldn't it be more fitting to use something a little more plausible? --Ehudshapira 05:14, 24 November 2005 (UTC)

How about this as a better example: In Plato's Socratic dialogue Meno, Socrates puts forth his theory that because the soul already knows everything and possesses all theoretical knowledge, people do not "learn" new information; rather, they simply recall it. This theory, of course, is useless on its face. I think it would make a perfect example of Occam's Razor. 147.9.166.236 08:04, 2 February 2006 (UTC)

desire to (non-)intentionally?
Um.. how could a space alien desire to non-intentionally knock down a tree? --Ott0 00:50, 29 November 2005 (UTC)


 * Probably by not looking at where it treads. --Hieronymus 13:18, 30 November 2005 (UTC)


 * Or by desiring to not look. :) --Joe Sewell 17:21, 19 December 2005 (UTC)

NPOV in Science
The phrase "at the same time, without Occam's Razor science does not exist" is clearly POV. Earlier in the article it is noted that the concept of the razor as a heuristic one, and as such it should be stated by use of NPOV. Occam's Razor is not the sole governing philosophy of science, but rather one of many. I have refrained from changing this for now in deference to those who have worked on this article for longer. The scientific method is not a at its simplest a method for making decisions it is a method for testing hypothesis, nothing more. Personally, and perhaps even in collectivity I would agree that Science is not possible without falsifiability and the scientific method, but I would not go so far as to say science is impossible without the razor especially considering that the razor relies on personal definitions and perceptions of complexity as well as an unstated statistical liklihood. -talonxpool


 * And the magic impersonal, stated criterion to select between underdetermined theories that would function as an alternative to the razor is?... I doubt that there exists even a viable personal, unstated alternative, for that matter, or at least one that would practically get you very far. Science is not merely a tool for testing hypotheses- it is a tool for shaping one's perception of the world, and for shaping a useful perception of the world you have no choice but to constantly go out on a limb and say, "okay, for the time being I'll risk /this/ set of assumptions being wrong, because methinks it has a good chance of proving to be right". Deciding on what hypotheses to test and how to go about gathering the data, sure, you can have a gazillion doctrines on that, ranging through positivism and Kuhn's paradigm shifts and what-have-you. But what to do with the data you already have, what to make of it here and now until new data comes along, I've yet to encounter anything other than Occam's razor that shows how to do that in a way that makes any sense. It being a heuristic is indeed a regrettable shortcoming, seeing as if we had an approach that could deal with all incoming data and was not a heuristic, we would have already been well on our way to omniscience. Take the example with the benevolent indetectible entities responsible for Newton's third law of motion - out of the "many governing philosophies of science" besides the razor you mentioned, which would you nominate for the role of a good representative and what exactly does it have to say about what we should expect in 2055, with the beings' regrettable demise? --AceMyth 03:07, 23 December 2005 (UTC)

Napoleon
Apparently, Napoleon said something like "Never attribute to conspiracy that which can be explained by incompetence," which is a nice way of phrasing it, especially since the Razor is an excellent weapon against conspiracy theories. I couldn't track down the quote, though. I thought one of you might know it or be able to find it. Dave (talk) 07:15, 22 December 2005 (UTC)


 * That's actually a variant of Hanlon's Razor. We've already got some stuff about it there, it says the derivation's unknown but presents some theories. Bryan 07:45, 22 December 2005 (UTC)

Sherlock Holmes
Does Holmes' "Once you have eliminated the impossible, whatever remains, however improbable, is the truth" correspond to this? I seem to also remember several quotes from Holmes about this; unfortunately, I have forgotten which adventures. If so, would it go in the Triva section?