Talk:Occam's razor

Suggestion to change image description.

The Razor has nothing to do with our understanding of the solar system model. Instead, it comes from infomation gathered from the orbit of Lo around Jupiter, and how it is delayed/accerated dependent on time of year. Please correct, as I have no other ideas for examples. Thankyou.

Syntax of physics example is incorrect I think

"For instance, classical physics is simpler than more recent theories; nonetheless it should not be preferred over them, because it is demonstrably wrong in certain respects." I don't think I understand the definition of "preferred" here. If you are talking about mechanics at non-relatavistic speeds Newtonian mechanics is still preferred. Maybe "accurate" would be better? — Preceding unsigned comment added by 98.249.51.38 (talk) 00:48, 27 May 2011 (UTC)

What Does Razor Mean?

I have been looking everywhere for an answer, but nothing seems to mention what "Razor" actually means. I of course understand it in context, but I have checked countless dictionaries and websites in vain to find a definition of "razor" which comes close to an kind of law or theory. Does anyone know why it is called "Occam's Razor?" LFStokols 08:18, 2 November 2007 (UTC)LFStokols

See razor. It is just a metaphor – there is not a well-defined technical concept named "razor" of which Occam's is an instance. The point of the metaphor is that the razor is a device that cuts away unnecessary protruding stuff from the theory, similar to how an actual razor cuts away protruding stubble. Hanlon's razor is a pun on Occam's one. –Henning Makholm 10:30, 2 November 2007 (UTC)

Thank you. It seems obvious now that you say it. LFStokols 22:13, 3 November 2007 (UTC)LFStokols

Apparently it's not so obvious (see "Misunderstands" section below)... I agree it's an important point, and one of the most obvious questions to ask (i.e. "why is it called Oc(/k)cam's razor?"). Even if there's disagreement as to where the 'razor' bit comes from, the arguments should be made. The razor as a metaphor to 'cut away excess complexities' arguement seems plausible, but the person in the "Misunderstands" section has a valid point, that the whole idea is not to posit these additional complexities in the first place! Can someone clear this up, or at least explain the arguments in the main article please??

I also could find no definition of "Razor" other than the above discussion, surely this should be described in the entries first paragraph? To me it seems more important than discussing the origin of "Occam" 194.106.46.76 (talk) 17:51, 15 December 2009 (UTC) Chris J Evans

Not sure if it helps for this discussion but in German it is called "Occams Messer" (i.e. Occam's knife), without the connotation of "shaving away" but instead with an emphasis on cutting or separating. DrCLN (talk) 15:56, 10 June 2010 (UTC)

The "Religion" part of the article

Its just a copy-paste from here http://etd.unisa.ac.za/ETD-db/theses/available/etd-05062009-112611/unrestricted/thesis.pdf p.90 among other pages. It was clear by the style of citing (author:year). Im not proficient on whats needed to do in this case, i will seek restructuration or removal. 190.158.4.187 (talk) 06:49, 16 May 2009 (UTC)

added {{copyvio}} tag Jasy jatere (talk) 11:26, 16 May 2009 (UTC)

Thanks for keeping an eye out for infringement. Evidence suggests that in this case the infringement may actually be reversed. First, note that the front page of the thesis is dated November, 2006. The third page is dated December 2006. This suggests publication after the latter of those dates. We take a chunk of page 90:

Some thinkers apply Occam's razor in the philosophy of religion to the existence of God; if the concept of God does not help to explain the universe, it is argued, God is irrelevant and should be cut away (Schmitt 2005:5). While Occam's razor cannot prove God's non-existence, it does imply that, in the absence of compelling reasons to believe in God, disbelief should be preferred.

In May of 2006, our article said the following (for convenience, I'm pasting without wikilinks):

In the philosophy of religion, Occam's razor is sometimes applied to the existence of God; if the concept of God does not help to explain the universe, it is argued, God is irrelevant and should be cut away (Schmitt 2005). While Occam's razor cannot prove God's nonexistence, it does imply that, in the absence of compelling reasons to believe in God, unbelief should be preferred.

We can trace the evolution of this passage. At the beginning of April, 2006, our article said this:

In the philosophy of religion Occam's Razor is sometimes used to challenge arguments for the existence of God: if there is no need for a "God" (to explain the universe), then the God construct is subject to elimination via Occam's Razor.

At the beginning of January, 2006, it said this:

In the philosophy of religion Occam's Razor is sometimes used to challenge arguments for the existence of God: if there doesn't seem to be a need for God (to explain the universe), then God most likely doesn't exist.

In August of 2005, it said, "In the philosophy of religion Occam's Razor is sometimes used to challenge arguments for the existence of God."

This material seems to have developed here naturally, and we seem to have had the seeds of it long before this thesis could have been published. --Moonriddengirl ^(talk) 02:32, 24 May 2009 (UTC)

Bias of section:

This section is an editorial advocating using Occam's Razor to advance a particular viewpoint. The fact that citations are given do not alter the misuse of the section to promote a point of view and it violates Neutral Point of View policy. The last paragraph especially illuminates the editorial intent. To be germane, this section should be rewritten to talk about use of Occam's Razor in the field of philosophy of religion and to eliminate bias, give examples of both sides of the debate. ProfGiles (talk) 18:44, 1 November 2009 (UTC)

The article is simply stating the use of Ockam's Razor in Philosophy of Religion. There is no debate of wether a god exists or not using Ockam's Razor. There are many articles explaining theories that support the existence of a god, this one does not. —Preceding unsigned comment added by 87.211.126.40 (talk) 12:21, 4 November 2009 (UTC)

In terms of the existence of God, Occam's Razor merely specifies that in the absence of evidence, God is likely not to exist. There is no undeniable 'evidence' of a God (such as frequent and unexplainable supernatural phenomena - although what is, and what isn't, unexplainable supernatural phenomena, has changed over time) so introducing a factor for which there is no justifiable reasoning is an unnecessary and unneeded complication that may result in inaccurate conclusions.

Occam's Razor is merely a rule that may prove useful in developing a hypothesis, and in the words of W. E. Johns; 'Rules are for the guidance of wise men, and the blind obedience of fools' - meaning you need to know when and when not, to use it. —Preceding unsigned comment added by 86.112.86.34 (talk) 14:29, 13 February 2011 (UTC)

Contradiction on basing current theories on unknown data

I have added the following phrase in the article:

On the other hand science cannot work on the assumption that future, unknown data will support a complicated model when a simpler one explains all existing data, since that would lead to the contradictory conclusion that future, unknown data is already known.

I felt the need to mention that explicitly in a paragraph that seems to advance the idea that Occam's razor's merits are in fact dubious:

In the scientific method, Occam's razor, or parsimony, is an epistemological, metaphysical, or heuristic preference, not an irrefutable principle of logic, and certainly not a scientific result. As a logical principle, Occam's razor would demand that scientists accept the simplest possible theoretical explanation for existing data. However, science has shown repeatedly that future data often supports more complex theories than existing data. Science tends to prefer the simplest explanation that is consistent with the data available at a given time, but history shows that these simplest explanations often yield to complexities as new data become available.

To me, this paragraph reads "yeah, Occam's razor is a cute little thing, but since history has shown it's wrong, we can go right ahead and ignore it". In other words, it's fair game to invent absurdly complex theories based on the assumption that data will appear in the future to support them – which it isn't, because you cannot know that data will appear in the future, or else you break the assumption that the unknown data is unknown.

My edit has been reverted, so I took the time to explain my reasoning here. Please return the courtesy before reverting again – or feel free to reword my phrasing if you agree in principle but don't like the way I put it. --Gutza ^{T T+} 13:15, 2 October 2009 (UTC)

Hello, I was the one who reverted your data, sorry, I meant no disrespect and I should have added something on this talk page. I don't share the disparaging view of Ockham's Razor you describe. However, the problem with your statement is that it philosophically doesn't make any sense to me. Where is the contradictory conclusion? If two theories, complex theory A and simple theory B both account for the existing data adequately, why should we prefer B to A? This is the philosophical problem of justifying Ockham's razor. Both theories assume that future, unknown data will support them. Indeed, the one of the important functions of scientific theories is to make predictions about the future. Imagine the following relationship between two variables in some scientific observation:

x: 0 1 2 3 4 5 6

y: 0 2 4 6 8 10 12

Now, imagine that theory A is

A) y = x^7 -21x^6 +175x^5 -735x^4 +1624x^3 -1724x^2 +722x

and that theory B is

B) y = 2x.

Both account equally well for this relationship of numbers, but they make drastically different projections about the value of y for x=7. Why is it contradictory to prefer A to B? In what way does B suppose "future, unknown data is already known" in any way above and beyond B?

--Palthrow (talk) 21:03, 2 October 2009 (UTC)

No problem with the revert, I simply defaulted to explaining myself upon getting reverted. First off, I agree that one of the most important functions of scientific theories is to make predictions about the future – moreover, I agree that a theory new theory really replaces an older one only when it matches new data existing theories don't match (such as here). However, I don't agree that in the example above theory A should be preferred, since that would mean the proponents of that theory implicitly claimed they knew the result for x=7 (which we obviously assume they don't know). Good example, by the way (seriously).

Accepting that the scientific method would agree with the equal sign you seem to put between theory A and theory B in your example would mean for instance that the Young Earth was a perfectly sound theory, sanctioned by the scientific community on par with modern evolution and cosmology. Indeed, instead of examining current data why not presume the existence of a God who created everything as to make it appear old? Well, I say because that would require the existence of a supernatural being we have no scientific evidence for. Your interpretation however accepts that based on the assumption that God will provide proof at a future time (even if that happens to be at the end of time or whatever).

Of course, we could now go down the path where "it's a matter of belief". But I don't want to turn this into a religious matter, I just used a different example to show why I think accepting unknown, future data on a belief basis contradicts Occam's razor's principle. --Gutza ^{T T+} 21:41, 2 October 2009 (UTC)

Science does not assume that future experiments WILL support a more complex theory over a simpler one, but science is certainly open to the possibility that future experiments MIGHT support a more complex theory. Science is open-minded toward all physical theories that are consistent with currently available data and the tendency among scientists is to consider how to design experiments to discriminate between different theories that tend to explain existing data equally well. The recent addition as it is currently worded represents something of a strawman fallacy and, since it is unsourced, appears to be original research.Michael Courtney (talk) 21:41, 4 October 2009 (UTC)

Of course science is open to evolve, I never meant to imply otherwise. My only beef here is related to the wording and the load of the following succession of phrases, as well as the corroborating support provided in the rest of that paragraph:

As a logical principle, Occam's razor would demand that scientists accept the simplest possible theoretical explanation for existing data. However, science has shown repeatedly that future data often supports more complex theories than existing data.

Again, the way I see it, this wording is very much supportive of an "anything goes" perspective which I strongly believe is in total opposition to what Occam's razor is in fact about. Yes, new evidence surfaces all the time. Yes, that new evidence topples old theories and validates new, more complex ones. That's the nature of the beast. But to start by assuming new data will topple existing theories and accept unnecessarily complex theories on the assumption that future data will validate them is, as I hinted above, a wildcard for any religious belief, or subjective belief in general, to be validated as a scientific "theory". Let's find a way to fix that and we'll all be a bit happier – I'm open to rewording that paragraph in a more neutral fashion, for instance. --Gutza ^{T T+} 22:36, 4 October 2009 (UTC)

You all seem to require a bit of "Occam 101". He did not want unnecessary and useless detail thrown into theories, or into the scientific process. He wanted logic and fact. The discussion above, about future data, is exactly what Occam's Razor is all about: he would have laughed you guys out of town.76.195.81.239 (talk) 03:02, 28 October 2009 (UTC)

Palthrow, you've made an error. In order for your math to hold, it must be "1764X^2" not "1724X^2". Shame on everyone else for not checking the math. Your point is nevertheless, well taken, Palthrow. Winick88 (talk) 07:13, 16 November 2009 (UTC)

Whoops, oh well, it makes no difference to the point being made. It is trivially true that for any finite set of numbers mapped like this, there is an infinite number of equations that satisfy it. -- Palthrow (talk) 17:01, 16 November 2009 (UTC)

I didn't even bother to read that equation, nevermind check it for errors becuase it's irrelavent. Rather than add the sentence that was reverted, I'd have edited the paragraph with which he disagreed as it has flaws in my opinion, since Ockam's razor is NOT dubious and says nothing about the future and shouldn't have to. I came here for another issue, so am now curious to see what the page says on this :)--Paddling bear (talk) 16:39, 15 September 2010 (UTC)

Changing prediction to say solution.

when you have two competing theories that have the same solution, the simpler one is the better.

We changed "prediction" to say "solution". —Preceding unsigned comment added by 68.225.62.139 (talk) 04:34, 30 October 2009 (UTC)

Creating solutions is mathematics, creating predictions is science. They are not the same. Mathematics uses the authority of proof through logic and science uses the authority of experiment on nature. Not really the same thing at all. And since the section was about the application of Ockham's to science and not mathematics it should say prediction. Also a scientific theory does't have to have a mathematical form, for example Darwin's ToE so "solution" does not apply. 207.30.5.99 (talk) 19:19, 19 November 2009 (UTC)

Not happy with the definition

Particularly, with the summary as "when you have two competing theories that have the same solution, the simpler one is the better." Even if it IS how this is popularly stated, the author should draw attention to it that this is an inaccurate and easily misunderstood way of putting the principle. If we always went with the simplest solution then most of our true, verified explanations would seem overcomplicated. This way of putting things can in fact be used as a justification for superstitious beliefs. This is not what the original statement meant however. What Occam's razor says is that we should discard circular ideas and add-ons, the ones that do not actively contribute to our explanation. For example, if you hear the wind blowing and it sounds like human speech, then the statement "it is a ghost" falls under Occam's razor because it contains many assumptions and implications about the afterlife etc. that have very little to do with the unexplained phenomenon at hand itself. Similarly the explanation that the changes in how air resonates are causing the voice might seem to include several similar pieces of information itself, however as these are all part of what we under stand to be true about our world, in that context, it requires very little leap of faith. Occam's razor does not say that "the simpler theory is the true one", rather what is says is "keep your theories simple". Can't we edit the article to be less misleading? - Zem —Preceding unsigned comment added by 15.195.201.91 (talk) 15:18, 30 October 2009 (UTC)

• I am always amazed at the definitions of Ockham's Razor that William of Ockham never wrote. Does anybody have the courage to observe that it is simply a blank sheet upon which people write their prejudices? Gkochanowsky (talk) 02:13, 28 April 2010 (UTC)

Removed the following from the Religion section

It must be noted, however, that in Ockham's time, the Church had tremendous influence on people and their ideas, and the Ockham's razor may be applied to today's subjects.

A clear attempt at discrediting the source through fallacious means (Circumstancial ad Hominem) —Preceding unsigned comment added by 189.14.242.184 (talk) 14:28, 25 November 2009 (UTC)

NPOV religion

I note there is a npov dispute and have to agree. Seems like original research, no reference, and where references are given, they are controversial and also they contradict one another, e.g. 72.2% vs 38%. Also, the data is applied dubiously - what does belief in a personal god have to do with relying on scientific explanations? It contains a tautology, ie most scientists prefer to rely on ... A scientist by definition should rely on ... regardless of belief in a personal or impersonal god. This whole section is in desparate need of a rewrite. If all the bias is removed, it will be a much cleaner and shorter version imho. —Preceding unsigned comment added by 41.240.210.79 (talk) 08:47, 28 November 2009 (UTC)

The concept of a personal god is a supernatural being that hears prayers and has the power to continuously affect the physical world. Invoking such intervention does not simplify the theory that the physical sciences provide to explain physical phenomena, and is therefore not justified using Ockham's razor. For that reason, it is relevant in this context. The data cited is not contradicting, it merely shows that while most scientists asked do not beleive in a god that can affect everyday life, many of them believe in a creator god that is no longer active. My point: The religion section is sound and unbiased. 83.249.215.241 (talk) 09:37, 24 January 2010 (UTC)

Confusion regarding Ockam's razor?

I may be wrong, but I think there is something wrong with section 3.1 as it currently reads. My problem is the author seems to be arguing that ockham's razor delayed the discovery that DNA is the holder of genetic information and not proteins, b/c researchers at the time thought that the protein hypothesis was simpler. I want to say ockham's razor shouldn't be based on what we THINK is simpler, but what IS actually simpler. The writer kind of got into that by saying that one could argue retrospectively that DNA is simpler, but then didn't continue.

I hope I effectively communicated what I feel is the problem with this logic. In short, ockham's razor is not ineffective b/c what we THOUGHT was simpler turned out to be more complicated.

"There are many examples where Occam’s razor would have picked the wrong theory given the available data." Ok, but even assuming that, it doesn't seem a fault of ockham's razor, but of the researchers perspective of simplicity.

Lastly, despite what I said, I think the section is good.

 —Preceding unsigned comment added by Grouphug (talk • contribs) 03:23, 5 December 2009 (UTC) 

Added Jargon template

The intro should be written in a manner that is easily understandable by people w/out prior knowledge of logic, philosophy, etc. Alcarillo (talk) 19:39, 11 February 2010 (UTC)

It is defined as "the principle that "entities must not be multiplied beyond necessity" and the conclusion thereof, that the simplest explanation or strategy tends to be the best one" and is explained as "When competing hypotheses are equal in other respects, the principle recommends selection of the hypothesis that introduces the fewest assumptions and postulates the fewest entities while still sufficiently answering the question." Seems pretty straightforward to me, no jargon there. -- Palthrow (talk) 21:47, 11 February 2010 (UTC)

So... let me see if I got this straight... You are saying that the article on Occam's Razor it too complex, and that a simpler article would be more desirable? Lol -- Big Brother 1984 (talk) 03:24, 13 February 2010 (UTC)

Let me ask both of you: do you have any prior knowledge of this term, and logic in general? If so, then it may seem a no-brainer what Occam's Razor means. Generally, these kinds of articles need a basic "who/what" starter that is easily understandable by the general public (ie people who probably don't know what "entities", "hypotheses", etc mean). For instance, the use of Latin is unnecessary in an opening statement because unless a reader understands Latin, it doesn't serve much purpose. These may help: WP:obvious, WP:tone WP:MTAA. Or not. Alcarillo (talk) 19:22, 18 February 2010 (UTC)

Please, by all means, clean it up and simplify it. But definitely leave the template up. It makes the article. --Nealparr ^{(talk to me)} 00:01, 2 March 2010 (UTC)

I think the article somewhat misses the point of the Razor.

Firstly, I have always understood it to be a razor, not in the sense of paring away the bad, but in finely, I might say nicely, dividing competing theorems in order to select one or the other.

This brings me to a second point of critique: Namely that the author appears to embrace the position that their are 'true' theories, and there are fallacious theories, and Occam's Razor cannot distinguish between them. If this were so, it would indeed be the case, but it is worth pointing out that many dispute that any theory can be 'truth evaluable' and indeed that the truth in any absolute terms (without a priori assumptions having to be made) is in any way accessible to any theoretical model. Even in mathematics, Godel's theory hints at the necessity of making some kind of arbitrary assumptive basis..there is no THEN without an IF.

I personally think, that Occam was more in touch with the humility of that position than we are today: he recognised that in order to prevent what we would now call theory-bloat, it was important to strip down a theory to the bare bones that would actually represent the actuality being modelled in a causal way.

Note that the razor states 'beyond necessity'. If the actuality of the data does NOT fit the model, or another model of more complexity fits it better, the razor is not in play as it were. Reluctantly we admit of more entities, out of sheer necessity!

Some have maintained that the Razor is indeed a justification for a Creator, in that at a stroke this explains everything. Extremely simply. Of course it does, but sadly it has no predictive power whatsoever. Ergo it fails Popper's test for a scientific theory.

Actually, a Creator doesn't explain anything at a stroke or even simply. In fact, it immediately introduces the problem of "who created the creator?". Now we have need of an additional entity which violates the principle of economy.

So my basic complaint, is that the whole article is written from a perspective of someone who confuses a successful and operational theory, with fact: Theories are always ad hoc, always subject to revision, nevera final truth. In such a scenario Occam's Razor ceases to become what it is sometimes purported to be, an arbiter of truth quality, and becomes what I believe it was originally intended to be, a pragmatic tool for the philosopher and scientist, to maintain discipline and economy in theoritic formulation. —Preceding unsigned comment added by 93.89.132.226 (talk) 00:51, 10 March 2010 (UTC)

Below Paragraph is not referenced

Can someone provide a good reference with evidence of factualness for the below statement or i'd like to ask it to be removed.

"It is often statistically more likely that a patient has several common diseases, rather than having a single rarer disease which explains their myriad symptoms."121.216.104.133 (talk) 00:44, 26 March 2010 (UTC)

Unhappy with statement about "simplest solution" in lead sentence

The very first sentence of the article presently reads, "Occam's razor (or Ockham's razor[1]), is the meta-theoretical principle that 'entities must not be multiplied beyond necessity' (entia non sunt multiplicanda praeter necessitatem) and the conclusion thereof, that the simplest solution is usually the correct one." I don't think that Occam's Razor says anything like, "the simplest solution is usually the correct one." That is just a popular misuse of the principle. A more correct statement is that, when presented with two competing theories supported by equal amounts of evidence, one may as well pick the simpler theory. In other words, there is no need to seek a very complicated explanation if there is no evidence for it, because a simpler explanation will do (at least, until more evidence becomes available). Therefore, I think that statement should be removed from the lead sentence of the article, or at least reworded to indicate that this is a popular interpretation of the Occam's Razor principle, which is not necessarily consistent with the original intent of the principle. See, for example, the discussion in the "Controversial aspects of the Razor" section of the article. Ketone16 (talk) 17:51, 29 March 2010 (UTC)

Or, more concisely, "Don't make up theories for which there is no evidence." Ketone16 (talk) 17:55, 29 March 2010 (UTC)

Wikipedia criticizes article as containing too much jargon.

I think what Wikipedia is complaining about is what was heretofore called "knowledge". —Preceding unsigned comment added by 72.38.186.77 (talk) 19:35, 29 March 2010 (UTC)Anasakta Baba (talk) 19:40, 29 March 2010 (UTC)

Rule of Thumb

Being Wikipedia I am sure you know full well that this connotation is derogatory to women who have been to college and taken a course in any history. Please take the "rule of thumb" out. Thanks. Try another way of explaining that doesn't involve this outdated and ridiculous phrase.

Beaten with a rod no wider than the width of a man's thumb. —Preceding unsigned comment added by 199.17.232.20 (talk) 17:42, 5 April 2010 (UTC)

Erm, no. See the WP article on Rule of thumb for references rebutting the etymology you cite, which is false and has been discredited. Jheald (talk) 23:29, 5 April 2010 (UTC)

Oh dear God. The Rule of Thumb dates it's origins to ruling with...you guessed it...a THUMB. Measurements. Not your ridiculous, fictional view (which historical accuracy is also widely fictional) of how women should be treated. 124.169.254.196 (talk) 05:59, 21 July 2010 (UTC) Sutter Cane

ha ha, I had the derogatory origins of 'rule of thumb' argued to me several times in college, only to read just a few years ago how false it is (the spurious origins and the much older use of measurements). Good job jheald, keep the PC from getting ridiculous. --Paddling bear (talk) 16:47, 15 September 2010 (UTC)

Unusual words are not necessarily jargon

The article may have flaws (and the ncited direct quotes are unfortunate), but it does not have jargon. The word "entities", for example, is an English word that is not used by a single specialty (whgich is what I understand jargon to be).

I always understood the "razor" in Occam's RAzor was referring to sharply distinguising between two theories.

Wymberley (talk) 03:00, 14 April 2010 (UTC)

Shouldn't there be a section for attempts to formalize the razor?

Seems like that be almost essential for the article but while there are plenty of stances on the razor, attempt to formalize it are given only a passing mention. 188.221.161.189 (talk) 00:58, 26 April 2010 (UTC)

In Literature and Writing?

Um, why is there a piece in their about Literature and Writing? Furthermore, what credibility does the website Hortorian.com have? Frankly, I do not see how a so called 'blog for young writers' could be credible.

93.107.200.242 (talk) 11:35, 11 May 2010 (UTC)

The section on Religion,

I have an issue with this text

"Ockham himself was a theist. He considered some Christian sources to be valid sources of factual data, equal to both logic and sense perception. He wrote, "No plurality should be assumed unless it can be proved (a) by reason, or (b) by experience, or (c) by some infallible authority"; referring in the last clause "to the Bible, the Saints and certain pronouncements of the Church" (Hoffmann 1997).[citation needed] In Ockham's view, an explanation which does not harmonize with reason, experience or the aforementioned sources cannot be considered valid."

It seems like an appeal to authority, for example Occam was from the 14th century so of course he had no idea of evolution etc, he would have likely believed in god because that /was/ the most sensible theory of the time. Also the section lack proper citation.

If it is to remain then it should first have proper citation and secondly include the view that Occam was a product of his time.

Like this on the BBC website "What would William have said?

William of Occam would not have agreed; he was a Franciscan monk who never doubted the existence of God.

But in his century he wasn't breaking the rule named after him. 14th century science knew nothing about evolution or how the universe came into being. God was the only explanation available.

What William would think if he lived now is another matter..."

http://www.bbc.co.uk/religion/religions/atheism/beliefs/reasons_1.shtml#section_2 —Preceding unsigned comment added by Kungfukats2 (talk • contribs) 09:17, 5 August 2010 (UTC)

I disagree. The article is simply stating the facts regarding Occam's stated opinion on the matter. I see no implication that his views were necessarily correct in this section. I don't think there's any need to insert speculation about what his beliefs might have been under different circumstances. Gukkor (talk) 02:57, 6 August 2010 (UTC)

Empirical justification

I thought the treatment insufficient, but grant that my expanded explanation would benefit from constructive criticisms!-Tesseract2 (talk) 20:31, 18 August 2010 (UTC)

Are there any citations for the first graf under "Empirical"? If it's an accepted school of thought, it should be referenced, yes? Lore Sjoberg (talk) 19:19, 11 March 2011 (UTC)

Hungry roommate

The fridge is hilarious.

It just needed to be said. Thmazing (talk) 05:15, 21 August 2010 (UTC)

Hilarious, yes. But I think it lacks a certain scholarly tone. I suggest that it be removed. —Preceding unsigned comment added by 151.207.246.4 (talk) 19:14, 30 August 2010 (UTC)

Personally I like it , and it's straight and to the point. The answer is of course that a group of Aliens did it. —Preceding unsigned comment added by 24.63.214.23 (talk) 04:27, 5 September 2010 (UTC)

Pictures like this are all over the article. I suppose that the woodcut of some piece of ancient folklore is appropriate, but it begs a more specific link to a pertinent article. Perhaps to the story of Persephone as an explanation for the changing seasons? The others, however, seem like lighthearted jokes and are not, in my opinion, appropriate in an address of key philosophical concepts. Replace the picture of the sun with one of William of Ockham, remove the baby and the tape measure (Seriously? "To Measure the razor's ability..."?) and maybe it'll look a little less like something from Uncyclopedia. IRSpeshul (talk) 15:51, 22 October 2010 (UTC)

Occam v. Ockham

Shouldn't the article use "Ockham" as the first spelling (with "Occum" in parentheses) since Ockham was the spelling of his origin (or is Occham an alternate spelling for the place too)? I counted the use, and although Ockham is used ~40 times and "Occum" is used over 60, I think we should still go with the place's true spelling. At the least the article should pick one. It's minor, but seems logical. --Paddling bear (talk) 16:58, 15 September 2010 (UTC)

The title of the article is Occam's razor. Article titles are typically, though not always, the first spelling used in an article, yet your recent changes do not list the title spelling at all (incidentally the spelling I am most familiar with, though perhaps it is not the optimal choice). It would be preferable to list Occam, if not as the main spelling, then as a spelling variant. Also, there are now three other spellings of Occam's razor in the lead section (Ockam's razor, Occham's razor, and Ockham's Razor) , none of which match the article title spelling, and one of which is not listed as a spelling variant in the lead sentence. Consistency of usage and identification of all spellings used seems preferable here, and I request you incorporate changes to that effect, and possibly an article retitle with redirect, if the new spelling is to remain. -- Michael Devore (talk) 21:14, 15 September 2010 (UTC)

The simplest and correct way to address this is to leave the heading as-is; "OCCAM" is the common usage. As long as the original "OCKHAM" is mentioned, this spelling need not be used again. My inclination is to vary the spelling between Ockham when talking of the man and Occam when talking of the "razor"--but that is only my personal whim.75.21.149.52 (talk) 06:55, 15 October 2010 (UTC)

Variation

I think the text boxes for each variation makes the article too long. I'm not agaist listing them all if anyone thinks it's useful, but don't see why we need a text box. Perhaps the original could be a text box if it's needed. My issue is that the original is an obscure Latin phrase that no one uses, and over the many years, people have taken the concept and reworded it. Since there isn't a modern specifc quote, do we need each person's attempt? The term 'species' also has a zillion definitions, yet my dictionary picks one or two and leaves the rest.--Paddling bear (talk) 18:04, 15 September 2010 (UTC)

Seconded. I agree 100% with Paddling Bear.75.21.149.52 (talk) 06:57, 15 October 2010 (UTC)

Marcus Hutter's result: request for verification

I am not familiar with his field, but I am skeptical that Dr. Hutter (or anyone for that matter) has "proved mathematically that shorter computable theories have more weight when calculating the expected value . . ." Looking only at the abstract for the paper "Optimality of Universal Bayesian Sequence Prediction for General Loss and Alphabet" we find the quote:

"Furthermore, for various performance measures, we show Pareto-optimality of � and give an Occam’s razor argument that the choice w�~�2^K(\nu�) for the weights is optimal, where K(�\nu) is the length of the shortest program describing �\nu."

This quote suggests to me that Dr. Hutter is \emph{using} the razor and not proving it.

I request that someone with better knowledge of the field look in to this.

The paper I referenced can be found here: http://jmlr.csail.mit.edu/papers/volume4/hutter03a/hutter03a.pdf

74.74.227.116 (talk) 19:09, 31 October 2010 (UTC)

Seconded. This article is specializing far too much. We need to branch out, creat new articles and if it does not meet that test then it ought to be omitted. That is assuming it isn't a subject that specifically invokes Occam.76.195.82.230 (talk) 22:32, 6 November 2010 (UTC)

There was no mistake in the sentence that you cite. It is the reference that you cite that is the wrong one. The actual reference is Marcus Hutter's book: "Universal artificial intelligence: Sequential decisions based on algorithmic probability" . According to Google Scholar this book has already been cited as a reference by 177 peer reviewed articles. You can read about it on Hutter's site: http://www.hutter1.net/ai/uaibook.htm

http://www.hutter1.net/ai/unipriors.htm Touisiau (talk)

Good news--this article has come closer to being simpler

Aside from my personal objection about the definition "the simpler it is the more probable its correctness", which is a gross misunderstanding of Occam, I have applied the razor to this article. You are lucky I left in the bare, relevant ramblings. This is not a plaything. This is one of the most offensively lengthy articles I have ever read. The images are stupid. Anyone coming in to revert, please post here about it or this will go to the admins.76.195.82.230 (talk) 05:28, 19 November 2010 (UTC)

This article will continue through its streamlining process, as stated by the above post. Discussion is clearly not something any editor wants here at the talk page, but I don't see why we have to start an edit war. This article is too long, confusing, specializing in ways it shouldn't and the stupid images do NOT HELP! Furthermore, though I will not remove it, I have major problems with the inclusion of Swinburne, one of the most idiotic philosphic writers, and also with the Probability section. That requires a probability-vis-a-vis-Occam's-razor page of its own.75.21.104.252 (talk) 17:57, 22 November 2010 (UTC)

If you guys have some more specific suggestions, maybe you could throw some tags up? Of course, there's always the risk that lazy editors will delete an imperfect segment rather than improve it...but I for one would welcome detailed critique of areas that need citations, need to be made more concise, belong in another article, etc.

As far as pictures go, I'll have to see better justification than just hating pictures before someone deletes almost all of the pictures in the article. Images are a powerful capability of Wikipedia, and used properly, they break up walls of text and provide decent summaries of sections. This is a big readability issue, and back's up all our amateur writings. All that having been said, I will again try to make images and captions interesting and relevant. -Tesseract2 (talk) 11:42, 23 November 2010 (UTC)

It seems what has been said about the pictures is that you'd as soon have irrelevant and silly pictures just because you can. Did it ever occur to you whether or not you should have them? Do they add anything? Do they illustrate the Razor? How does a baby illsutrate it?75.21.104.252 (talk) 23:34, 5 December 2010 (UTC)

"the simplest explanation is more likely the correct one"

Is an incorrect summary of Occam's R. Can those IPs please STOP removing this as it misleads readers. Vexorg (talk) 15:41, 2 December 2010 (UTC)

You should clarify what words exactly you are claiming to be "incorrect". I have tried to remove the summary of the simplest explanation, but editors here, having been schooled in that fallacy, keep putting it back. Rather it should say "The explanation with the least B.S. is probably the best one." THAT is what Ockham meant.75.21.104.252 (talk) 23:36, 5 December 2010 (UTC)

The sentence is perfectly clear what is incorrect. Vexorg (talk) 23:35, 16 December 2010 (UTC)

Religion, Philosophy, Statistics

I think a lot of this is quite relevant to Occam's razor and its use. Certainly relevant enough not to be mass deleted. Some of this stuff is for sure POV and uncited, and that should be deleted or minimized. A more careful combing through is in order - which I will try later or you can try.-Tesseract2 (talk) 13:45, 20 February 2011 (UTC)

razor not particular to atheism

An ip-editor removed the atheism template saying "anti-gods is merely one application" which OrangeMarlin reverted saying "atheism is not "anti-god"". While not agreeing with the "anti-god" bit, I do agree that the usage of razor in atheism is "merely one application". Having the atheism side-bar here gives "undue weight" to atheism. Accordingly, the atheism template should be removed. (and the link to Occam's razor should be removed as well.) Hpvpp (talk) 10:50, 27 March 2011 (UTC)

I'll agree to that. Fleetham (talk) 14:53, 27 March 2011 (UTC)

I'm in agreement, I just don't think anonymous editors should be removing content without explanation. Just a personal bias. And sorry, but atheism is NOT anti-god, especially since most atheists, like myself, know that god doesn't exist, so it's hard to be anti something that doesn't exist. It had nothing to do with my reverting the anonymous user, just a comment to his pejorative labeling of atheists as "anti-god." Occam's razor is a logical argument in discussions about the existence of god, but usually in the scientific sense. Like in creationism where the religious types bend and twist and turn to attempt to explain fossils, whereas simple evolution explains it quicker and easier. Occam's razor. But really, it's a philosophy of science issue rather than atheism. OrangeMarlin ^{Talk• Contributions} 17:12, 27 March 2011 (UTC)

(i) Considering the responses here, I removed the template from the article and the article from the template.

(ii) Considering OrangeMarlin's comment about anonymous editors: I worry that this is one of the kinds of behavior that puts off new editors. See several discussions at Wikimedia. Hpvpp (talk) 21:17, 27 March 2011 (UTC)

Too the poster of the thread; Please use proper grammar. —Preceding unsigned comment added by 82.36.122.5 (talk) 15:48, 13 May 2011 (UTC)

Empirical: Original research (and perhaps wrong too)?

The second paragraph under "empirical" seems to me to be original research:

In the history of explanations, this cannot be the case. Imagine the correct explanation of a phenomenon is found: that explanation was always competing with an infinite number of (relatively speaking) infinitely more complex alternatives. If this premise is granted, it amounts to a necessarily greater number of more complex, but incorrect theories for any given correct theory. This suggests an empirically justified bias towards simplicity in a theory.

Fortunately, someone added a "citation needed". Seems to me that this paragraph is

• unsupported
• difficult to understand
• wrong besides (but I'm not sure I understand it)

Dr Smith (talk) 00:08, 29 March 2011 (UTC)

After some editing, it is now more clearly a discussion of what ad-hoc hypothesizing has to do with the empirical use of Occam's Razor. Lemme know your thoughts.-Tesseract²(talk) 03:06, 29 March 2011 (UTC)

I'll start with the first sentence of the new text.

Occam's razor has gained strong empirical support as far as helping to converge on correct theories (see "Applications" section below for some examples).

Scientific theories are not "correct" in any meaningful way; at best, a scientific theory is (a) falsifiable, and (b) not falsified yet.

Next sentence:

This does not, however, answer the question of why reality favours simpler explanations.[20]

I looked through the reference [20], but I could not find that it supports the sentence it is attached to. It's quite a long reference. It seems a pretty strong statement to say that reality favors simpler explanations. That's not what Occam's razor says. I doubt that any scientist would say that the tiny parcel of reality that he/she has devoted his/her life to studying is simple.

Next paragraph.

Even if Occam's razor is empirically justified (see "Applications" section below), so too is the need to use other "theory selecting" methods in Science. For instance, in order to have even justified Occam's razor, theoretically a scientist must first identify "the correct explanation" to gauge its complexity. Obviously this must be accomplished using other aspects of the Scientific method besides the razor itself (or else we would be making a circular argument to support the razor). Thus, to measure the razor's (or any method's) ability to select between theories, we must be sure to use a different, reliable "theory selecting" method for corroboration.

Science does not ever identify the correct explanation. Science is tentative. Always.

The comment about a circular argument seems condescending.

Next paragraph.

One should note the related concept of overfitting, where excessively complex models are affected by statistical noise, whereas simpler models may capture the underlying structure better and may thus have better predictive performance. It is, however, often difficult to deduce which part of the data is noise (cf. model selection, test set, minimum description length, Bayesian inference, etc.)

The "overfitting" stuff seems so loaded with weasel words that it is nearly devoid of meaning.

That's all for now.

I don't mean to be harsh; all the above is just my opinion. Of course.

Dr Smith (talk) 04:01, 30 March 2011 (UTC)

I greatly appreciate your input. I tried to make the quicker fixes first, as explained in the edit summary. That talk of over-fitting was not my doing. I do not understand it, and would not miss it.

Yes, we should discuss truth and science. That is, I am not the first to say that neither humans, nor their science, seem able to tell when they have formulated "correct" theories. Still, it does seem that this is quite different from claiming that neither could ever be "correct in any meaningful sense". For example, I would say that we may well be correct that the moon orbits the earth, even if we will never know if we are correct because of Hume's problem of induction.-Tesseract²(talk) 05:10, 30 March 2011 (UTC)

Yeah, interesting stuff, isn't it.

You're right about my "correct in any meaningful way" bit. There are plenty of ways a scientific theory could be called "correct". For example, we could say a theory is correct if it is useful.

What I meant, though, is somewhat different than Hume's problem of induction, and perhaps somewhat similar to our inability to be able to tell when a theory is correct.

In the case of the moon orbiting the earth, yeah, I think we have that one covered. But what are the equations that describe the motion? This is where things get interesting. Newtonian mechanics works really really well, and augmented by Einstein, works fabulously well. Nonetheless, there may be room for even further adjustment. Consider the Pioneer anomaly and the flyby anomaly, for a couple of examples. Are either of these new physics? Maybe, maybe not. But my point is that science is open to the possibility that we are leaving something out. Maybe something huge.

So, is our current theory of gravity useful? Absolutely yes. Is it correct? Well, what do we mean by "correct"? Does the moon go around the earth? Yes; got that one covered. Will our understanding of the universe change in some deep and fundamental way that may tweak our current best guess at the equations of motion? Perhaps; science cannot rule it out.

Dr Smith (talk) 23:17, 1 April 2011 (UTC)

As I understand it, you are wary of my use of "correct", especially in a philosophical context. I get that. But I think we too often mistake the nature of the human condition (we are never certain) with the nature of the world as we actually believe it to be (things are true sometimes, theories are correct). We can only ever talk about what we are convinced is correct, and so we have: the earth and planets may well revolve around the sun. My point is that, the ever present shadow of skepticism not withstanding (e.g. wait, what IS skepticism really. For that matter, how sure can we be there is an earth? etc. etc.) I think there are clearly times that it is justifiable to speak with confidence that we have discovered a truth. For many other theories, mind you, like evolution.

Note too that I say Occam's "helps converge"; it is one tool of many that will help us reach the truth. Although, again, we will never be beyond capable of doubting that we have acquired truth- not even when we have it.-Tesseract²(talk) 02:12, 2 April 2011 (UTC)

Yes, I am more than wary of using the word "correct" to describe a scientific theory. A scientific theory can be

• accepted
• useful
• obvious
• widely regarded
• often cited
• etc.

But, by its nature, science is tentative and always willing to revise and rewrite, if other evidence presents.

Contrast with arithmetic, which is (provably) correct.

A scientific theory attempts to model part of the real world, and calling a scientific theory correct strikes me as dogmatic.

Since you mention evolution, yeah, it seems Darwin got the big picture right. But "survival of the fittest" (natural selection), seems an oversimplification. Consider The Selfish Gene for example. And, it seems like luck plays a huge role in the survival of species, and civilizations, and individuals. Sorry I don't have a reference for this, but, consider the Spanish Armada if you doubt the historical importance of luck. Dr Smith (talk) 19:59, 3 April 2011 (UTC)

IMO there is a conflation of "theories" and "explanations" which should be cleaned up first. -- Hpvpp (talk) 04:33, 4 April 2011 (UTC)

That may be something we have to deal with next...

I am not sure we are understanding each other, partly because I feel like I agree with your points. "A scientific theory attempts to model part of the real world"; I agree, and if there is a real world, there is such thing as a "Correct" and "Incorrect" models. Or is that where you disagree? Perhaps you would say no model could be correct - not even heliocentrism, not even accidentally?

I also believe that there are degrees of certainty, ranging from a slight balance of probabilities (51%) to being beyond reasonable doubt (99%ish). Although, nothing is ever beyond a shadow of possible doubt (100% certainty). Perhaps you would say we should never use the word "correct", even to talk about things that are beyond reasonable doubt? I think that would be excessive skepticism - or at least failing to draw an important line during communication. I do not think science needs to get so tentative that we need to say "Well, we are convinced of the useful beliefs that the earth orbits the sun, that evolution is broadly correct, that we have lungs and hearts, etc... but we should not use the word "correct" to discuss such theories." To me, when something is beyond reasonable doubt, it is appropriate to begin using language of possible correctness.

I see another potential issue here. The sentence is changed if we say "Over the years, and after much new data, heliocentrism... has become the most accepted model" versus "heliocentrism... has emerged as the most likely model". In one case, we make no mention of the existence of truth, even in theory, and we speak only of agreement. In the second case, we are talking about the truth as much as we ever can. This is why I talk about some theories being "correct", rather than merely "popular". There is an important difference, and I do not think it dogmatic to make the distinction.

I believe that some models and explanations are correct sometimes. I believe that we can never know which ones are correct. Yet I also believe it is more than justifiable, even necessary, to use language like "correct" to discuss explanations that are extremely far from reasonable doubt.-Tesseract²(talk) 15:32, 4 April 2011 (UTC)

For the "... if there is a real world" bit, I'm content to completely ignore the brain-in-a-vat possibility as it is not particularly useful to this discussion.

I am also content to agree that it is correct that the earth goes around the sun instead of vice-versa.

Note there are several heliocentric models:

• Copernicus (same as ancient Greeks) - sun is center of the universe
• Kepler - sun is on one of the two foci of an ellipse, which is at the center of the universe
• modern - planets go around the sun in generally elliptical orbits; the sun's center is near the one of the foci of an ellipse, all the orbits wobble a bit due to cross-interactions of gravity, among other things; our sun is one of many stars, in one of many galaxies, nothing special about it (from the point of view of astronomy anyway).

Note also that as history marches on, this theory has gotten more and more complex. Even the meaning of the word has changed; I pretty sure you meant the modern view of heliocentric, not the original one.

Is heliocentrism correct? Yes, if all the word means is that the earth goes around the sun instead of vice-versa. However, when we consider the details, we have to bring in the theory of gravity, the theory of relativity, dark matter, and probably even all of modern cosmology. I don't expect an expert in the field would be willing to tag this conglomeration as "correct" ... there are simply too many things we don't know.

Maybe our discussion boils down to whether "correct" is an absolute adjective or a comparative adjective.

I hear it both ways, but in my own use, it is an absolute adjective:

It is correct to say that 2 + 2 = 4. It is the same amout of correct to say 1 + 1 = 2.

If someone says

• 1 + 1 = 1.99, and/or
• 1 + 1 = 1.999

which is more correct? Neither, they are both wrong. I avoid saying "more correct"; I use "more nearly correct" instead.

You ask whether I would say that no model could be correct, not even heliocentrism, not even accidentally. In broad strokes, sure, models can be correct. But only if we don't look too closely. If we look closely (at heliocentrism, for example) we find that either

• the "broad strokes" version has been falsified (the center of the sun is not at the center of mass of our solar system), OR
• the fully detailed "standard model" is pushing the envelope of what we know.

I agree there are degrees of certainty, but this is not to say that I believe there are degrees of correctness. I believe there are things that are true beyond a shadow of a doubt; mathematics works in this realm, for example.

Dr Smith (talk) 03:43, 5 April 2011 (UTC)

I have updated the writing in the Empirical section to try and honour your reservations. I agree that math and deduction can yield certain results. I also very much like your point about "being broadly correct", that was more where I was coming from - things get terribly unproductive when a person will not grant that the earth at least orbits the sun, in the plainest senses of the word. I just wanted to defend science's right to use words like "fact" at some broad, shallow, laymen, public level of discourse. That can actually be quite important.

Ultimately I agree that no model is likely to map to the universe well enough to be called fully correct on all details. You have at least convinced me there is no need to throw that word lightly around on the Razor's page.-Tesseract²(talk) 05:25, 5 April 2011 (UTC)

The razor is not a theory and therefore cannot be falsified.

I have rewritten the first paragraph in terms of support and rejection of hypotheses. Also, I have deleted the last sentence (“Simply put, Occam's razor would be falsified if there was a positive correlation between (a) a theory's correctness and (b) the number of new assumptions it requires.”), because it misleadingly suggests that the distinction between truth and falsity is a matter of degree. -- Hpvpp (talk) 01:52, 1 April 2011 (UTC)

I like it. That's a much better way of putting it.-Tesseract²(talk) 02:47, 1 April 2011 (UTC)

Picture

It is coherent to add the involvement of Leprechauns to any explanation, but Occam's razor would prevent such additions, unless they were necessary.

Does anyone agree that this picture of a Gnome (It's currently on the page under Justifications/Testing the razor) is better than the earth/sun picture currently in the lead? Fleetham (talk) 13:36, 1 April 2011 (UTC)

Without a doubt. It is a much stronger example of how useful the razor can be, since it gets tons of exercise when it comes to pseudoscience (whereas as more scientific theories normally end up competing more closely).

Unfortunately we get IPs deleting the image BECAUSE it's leprechauns. They assume it's some degree of not taking the subject matter seriously. That is why I moved the earth example back to the lead - to set the tone unambiguously.=Tesseract²(talk) 13:51, 1 April 2011 (UTC)

Well maybe something that isn't leprechauns then? "It's coherent to involve some celebrity in every explanation..." maybe? Fleetham (talk) 15:49, 4 April 2011 (UTC)

The razor does not help in any way of finding the model of the solar system, instead it comes from the observations taken from the orbit of Lo around Jupiter. —Preceding unsigned comment added by 82.36.122.5 (talk) 15:50, 13 May 2011 (UTC)

movie the big bang 2011 movie

Is ab Occam's razor and Lex parsimonae etc and dialogue talks ab that a good deal (Antinio Banderas and Sam Elliott). q.v. etc big bang or big creep ? 69.121.221.97 (talk) 15:08, 25 May 2011 (UTC) and see also God Particle / Higgss Boson

Merger

It seems a merger may be in oder. Consider that...

• The "Parsimony" page is short except for...
• Discussion of its relation to science, where it is often used synonymously with the razor
• Even in the lead, Occam's Razor is said to be known also as the law (or principle) of parsimony

This seems to be one in the same practical bias tool. Depending on discussion, I am interested in redirecting that page here, and working the information into the appropriate sections.-Tesseract²(talk) 14:09, 1 April 2011 (UTC)

Perhaps it should be the other way around and the Parsimony page can then link to Occam's Razor and Morgan's Canon as alternative guises (as in Reber's 1985 The Penguin dictionary of psychology). -- Hpvpp (talk) 04:30, 4 April 2011 (UTC)

2 weeks and no objections! The Occam's Razor page was way bigger, so I merged Parsimony here. I was very careful, and I think I managed to port over every single link, fact, and logistical detail of the other page.-Tesseract²(talk) 04:27, 15 April 2011 (UTC)

Uh, I objected. -- Hpvpp (talk) 06:24, 15 April 2011 (UTC)

Right, sorry. After 2 weeks, one objection, and I think I had good reason not to let it delay my work. Your suggestion was basically to merge Occam's Razor into a page that was less than 1/5th the size (Parsimony) rather than bring those details over. If you really want to, it is not too late to begin discussing whether you should rename this page so that the content on this "Occam's Razor" could fly under the banner "Parsimony". Still, I do not think that is worth discussing (the Razor and Parsimony are basically synonymous in the literature, so the end result would be the same).-Tesseract²(talk) 13:36, 15 April 2011 (UTC)

I think rather that the Principle of Parsimony is a higher order concept than either Occam's razor or Morgan's Canon. Specifically, I think that these two are but applications of the principle. Somebody will need to address that (sometime). -- Hpvpp (talk) 02:51, 16 April 2011 (UTC)

A couple complaints/concerns

1. Heliocentrism is a problematic example. Historically, it is well known that Copernicus's model was just as complex, originally, as was the model it was trying to displace. At a deeper level, heliocentrism is simpler only if you ignore various things that would have preoccupied people in the past. It is not clear to me that our current theories of planetary rotation, for example, are "simpler" than Ptolemy's. (General Relativity ain't exactly simple, except in the same way that you can reduce it to a conceptually simplistic "idea" if you want to be very incorrect about it, which you can also do with Ptolemy's approach, if you cared to.) The fact is, we have better reasons to believe in heliocentrism than Occam's razor alone. It's not a great example. The only reason Occam's razor works for heliocentrism is because we have amassed huge amounts of empirical evidence in favor of other theories. Not because they are "simpler." ("Simpler" is often in the eye of the beholder, in any case.)

2. The "empirical" section states with regards to testing of the razor that it has basically won out over time. It cites no evidence for this. It gives no impression as to what kinds of evidence it is considering and what kinds it is not. It strikes me (as in the example I give above) that determining whether the "simpler" answer won out is not always straightforward. Then moving on to supernatural leprechauns is, I think, a straw man argument. --Mr.98 (talk) 12:23, 8 April 2011 (UTC)

Re 1. Actually the problem is worse: GR says that any frame of reference is valid. The question of which rotates around which becomes meaningless; all that happens is that you get simpler equations in some frames William M. Connolley (talk) 10:01, 12 April 2011 (UTC)

1. Connolley - I am not clear about that last comment... so would you say GR (general relativity?) comes down on either side of the question "Does the earth orbit the sun or vice versa?"

1cont. Mr.98, you mention that "simpler" is in the eye of the beholder. That may be true if we use the term ambiguously, but there are ways to pin down what we mean by "simpler". Actually, I have yet to bring over, to the Wikipage, the relevant discussion from the Standford Encyclopedia of Philosophy's entry on "Simplicity". You are right to point out that these could become issues with the formulation of the Razor itself, and they would be relevant if anyone got around to it.

1cont. I also noticed that you say it is not clear to you that, today, current theories of planetary rotation are simpler than Ptolemy's. I think that is exactly the right question to ask, because the example on the page is discussing the modern justifiability of the preference for heliocentrism. It seems to me that, in some sense, we still only believe in it due to the Razor. That is, each of us is appealing to the simplest explanations when we believe that we are not deceived in thinking science has "amassed huge amounts of empirical evidence". Couldn't all our 'evidence' be somehow mistaken? Isn't it, today, partly through the use of Ockam's Razor that we believe heliocentrism despite that possibility? If not, perhaps we could discuss other examples, but I tend to think it's good enough.

2. Issues with the formulation of the Razor and "simplicity" in general notwithstanding, I am not sure what evidence you mean the "Empirical" section is not providing. The point is that ad-hoc explanations can save any theory, meaning the Razor (or some appeal to simplicity) is needed to ultimately reject them. Leprechauns are not a straw man here, they are the most dramatic example of this: a coherent and possible explanation that is ultimately unhelpfully complex.-Tesseract²(talk) 15:50, 12 April 2011 (UTC)

1: no, I'd say what I said: The question of which rotates around which becomes meaningless and then, I suppose, amplify that with "unless you specify which frame of reference you are using" William M. Connolley (talk) 17:05, 12 April 2011 (UTC)

Move paragraph from Overview into History, please?

The paragraph in "Overview" that begins with the sentence: "Occam's razor is attributed to the 14th-century English logician, theologian and Franciscan friar Father William of Ockham (d'Okham)..." bogs down that section. It would, however, be a great start to the "History" section. (The History section currently starts awkwardly with a lengthy quote, which at first glance looks not like a quote but like accidentally indented text.)

Shall we move the paragraph into History? Reverence Still (talk) 20:19, 16 June 2011 (UTC)

Image and description inappropriate

Everything revolves around everything else. That's the simplest, most Occam's Razor friendly explanation. Because all motion is relative, the Earth can be considered motionless with all the heavenly bodies revolving around it. The explanation for the sun revolving around the earth is no more complex than its opposite. Please, don't anyone knee-jerk reverse this edit until you have thought about it.