# Occam's Razor - self referential? **URL:** \ **Category:** Great Debates\ **Created:** [August 1, 2001, 1:20pm UTC](https://boards.straightdope.com/t/occams-razor-self-referential/74465 "2001-08-01T13:20:11Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![Mangetout](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mangetout/32/19_2.png) [@Mangetout](https://boards.straightdope.com/u/Mangetout)\ **Post date:** [August 1, 2001, 1:20pm UTC](https://boards.straightdope.com/t/occams-razor-self-referential/74465/1 "2001-08-01T13:20:11Z")
There don’t seem to be many GD threads where Occam’s Razor doesn’t get invoked at some point, but anyway: > [@](#): > > The explanation requiring the fewest assumptions is most likely to be correct Or words to that effect. How are we to know that Occam’s razor is reliable in determining **real truth**? don’t we have to first accept that in itself it is the simplest explanation? Now sure, we can theorise, test and match our findings against our theories, and Occam’s razor **seems** to be true, but how can we test it? Surely we eventually fall into the cycle of: “My observations are reliable because they are supported by the principle of Occam’s Razor”… “Occam’s Razor is reliable because my observations have shown it to be correct” (I’m not trying to assert that it _isn’t_ reliable, I just want to know how we can _know_ it’s reliable) ---
**Author:** ![kabbes](https://avatars.discourse-cdn.com/v4/letter/k/e99b99/32.png) [@kabbes](https://boards.straightdope.com/u/kabbes)\ **Post date:** [August 1, 2001, 1:22pm UTC](https://boards.straightdope.com/t/occams-razor-self-referential/74465/2 "2001-08-01T13:22:11Z")
We can’t. It’s axiomatic. That’s the point. pan ---
**Author:** ![ultrafilter](https://avatars.discourse-cdn.com/v4/letter/u/3d9bf3/32.png) [@ultrafilter](https://boards.straightdope.com/u/ultrafilter)\ **Post date:** [August 1, 2001, 1:39pm UTC](https://boards.straightdope.com/t/occams-razor-self-referential/74465/3 "2001-08-01T13:39:21Z")
As I may have said in an earlier thread, Occam’s razor is not an observation. It’s a decision procedure, used to pick between competing theories. A variation of Occam’s razor that applies to decision procedures certainly can be applied to the razor itself; however, as it (Occam’s razor) has been very successful in building a consistent and accurate scientific worldview, it’s very difficult to imagine how it could begin to fail. ---
**Author:** ![Mangetout](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mangetout/32/19_2.png) [@Mangetout](https://boards.straightdope.com/u/Mangetout)\ **Post date:** [August 1, 2001, 1:55pm UTC](https://boards.straightdope.com/t/occams-razor-self-referential/74465/4 "2001-08-01T13:55:23Z")
> [@](#): > > \*Originally posted by ultrafilter \* > \*\*A variation of Occam’s razor that applies to decision procedures certainly can be applied to the razor itself; however, as it (Occam’s razor) has been very successful in building a consistent and accurate scientific worldview, it’s very difficult to imagine how it could begin to fail. \*\* Suppose there really _ **was** _ an Invisible Pink Unicorn. ---
**Author:** ![kabbes](https://avatars.discourse-cdn.com/v4/letter/k/e99b99/32.png) [@kabbes](https://boards.straightdope.com/u/kabbes)\ **Post date:** [August 1, 2001, 1:59pm UTC](https://boards.straightdope.com/t/occams-razor-self-referential/74465/5 "2001-08-01T13:59:00Z")
That would definitely qualify for a slot on the “World’s Biggest Ironies” program. pan ---
**Author:** ![Mangetout](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mangetout/32/19_2.png) [@Mangetout](https://boards.straightdope.com/u/Mangetout)\ **Post date:** [August 1, 2001, 2:32pm UTC](https://boards.straightdope.com/t/occams-razor-self-referential/74465/6 "2001-08-01T14:32:45Z")
Actually, to answer my own question; if there really was an invisible pink unicorn, then there would be evidence, if the evidence is of some nature that we will never have any way of percieving or detecting, then to all _practical_ intents and purposes, the unicorn isn’t ‘real’ in that it doesn’t interact with our world. ---
**Author:** ![AHunter3](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/ahunter3/32/368_2.png) [@AHunter3](https://boards.straightdope.com/u/AHunter3)\ **Post date:** [August 1, 2001, 2:51pm UTC](https://boards.straightdope.com/t/occams-razor-self-referential/74465/7 "2001-08-01T14:51:27Z")
Occam’s Razor is an excellent tool in an environment where one has sufficient facts. It tends towards oversimplification in environments where certain important data may not yet be available. Consider the rather silly theory that the earth revolves around the sun, and the additionally silly argument that the reason it looks like the sun revolves around the earth instead is due to the fact that the earth rotates as well as revolves. The uneducated everyday 5th Century farmer could be said to be using Occam’s Razor in dismissing such silliness, yes? I would also suggest that Einsteinian physics would suffer from razor cuts inflicted by a sensible Newtonian observer. In both example cases, you could argue that observations did or could be made that would deflect the razor, but only if the person weilding the blade is willing to continue considering the more complicated explanation long enough to examine them fairly. ---
**Author:** ![epolo](https://avatars.discourse-cdn.com/v4/letter/e/b487fb/32.png) [@epolo](https://boards.straightdope.com/u/epolo)\ **Post date:** [August 1, 2001, 2:58pm UTC](https://boards.straightdope.com/t/occams-razor-self-referential/74465/8 "2001-08-01T14:58:24Z")
I vaguely remember reading somewhere that someone had done a test of Occam’s razor and found that it **didn’t** really work. I’ll see if I can find a cite for this but whatever I read was years ago. ---
**Author:** ![Mangetout](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mangetout/32/19_2.png) [@Mangetout](https://boards.straightdope.com/u/Mangetout)\ **Post date:** [August 1, 2001, 3:04pm UTC](https://boards.straightdope.com/t/occams-razor-self-referential/74465/9 "2001-08-01T15:04:16Z")
> [@](#): > > \*Originally posted by AHunter3 \* > \*\*In both example cases, you could argue that observations did or could be made that would deflect the razor, but only if the person weilding the blade is willing to continue considering the more complicated explanation long enough to examine them fairly. \*\* Very good point, thanks ---
**Author:** ![Podkayne](https://avatars.discourse-cdn.com/v4/letter/p/edb3f5/32.png) [@Podkayne](https://boards.straightdope.com/u/Podkayne)\ **Post date:** [August 1, 2001, 3:31pm UTC](https://boards.straightdope.com/t/occams-razor-self-referential/74465/10 "2001-08-01T15:31:25Z")
Speaking scientifically, Occam’s razor doesn’t reveal **real truth** , because science doesn’t reveal **real truth**. Science is nothing more than the most accurate way to describe the physical universe that we’ve figured out yet. Occam’s razor is a guiding principle, not an absolute rule–something like the concept of “elegance”, an aestetic quality of simplicty and robustness that is desired in a good scientific theory. ---
**Author:** ![Whack-a-Mole](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/whack-a-mole/32/141_2.png) [@Whack-a-Mole](https://boards.straightdope.com/u/Whack-a-Mole)\ **Post date:** [August 1, 2001, 3:34pm UTC](https://boards.straightdope.com/t/occams-razor-self-referential/74465/11 "2001-08-01T15:34:24Z")
> [@](#): > > \*Originally posted by AHunter3 \* > Occam’s Razor is an excellent tool in an environment where one has sufficient facts. It tends towards oversimplification in environments where certain important data may not yet be available. > > …you could argue that observations did or could be made that would deflect the razor, but **only if the person weilding the blade is willing to continue considering the more complicated explanation** long enough to examine them fairly. Great points AHunter3 but I have a bit of trouble with the part I bolded in the quote above. By your examples the 5[sup]th[/sup] century farmer would indeed be correct in applying Occam’s Razor and saying the sun revolves around the earth. He’d be wrong, of course, but as far as anyone knew at that point it was true and seemed to make the most sense. _However_, it does not take someone intentionally exploring more complex explanations to arrive at the right answer. What in fact happened was people started looking at the stars and planets and tracked their movements. When it came to other planets’ movement across the sky they saw some very weird behavior. Some planets seemed to stop, reverse direction for a bit and move forward again. Some explanations were put forward as to how all of this worked using a heliocentric view of the solar system. Unfortunately these explanations were quite convoluted. Eventually, some bright guy figured out if you had the earth orbiting around the sun _then_ you got back to the simplest answer that fit the observations (Occam’s Razor). After a bit of a hassle with his church people eventually came to see that this was indeed the way of things. I believe Occam’s Razor is a good and useful tool as long as it is understood that it does not make answers correct in and of itself. I see no use in continuing to consider more complicated explanations. I do see a use in continuing observation and experimentation and holding those results against your previous hypothesis. If something no longer fits you readjust and maybe come up with a more complicated version than you previously had but Occam’s Razor still applies! You simply keep the simplest explanation you can that fits the facts at hand. ---
**Author:** ![Whack-a-Mole](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/whack-a-mole/32/141_2.png) [@Whack-a-Mole](https://boards.straightdope.com/u/Whack-a-Mole)\ **Post date:** [August 1, 2001, 3:38pm UTC](https://boards.straightdope.com/t/occams-razor-self-referential/74465/12 "2001-08-01T15:38:15Z")
I said: > [@](#): > > Some explanations were put forward as to how all of this worked using a **heliocentric** view of the solar system. That should read: “… **geocentric** view of the solar system.” Sorry about that. ---
**Author:** ![erislover](https://avatars.discourse-cdn.com/v4/letter/e/71e660/32.png) [@erislover](https://boards.straightdope.com/u/erislover)\ **Post date:** [August 1, 2001, 3:45pm UTC](https://boards.straightdope.com/t/occams-razor-self-referential/74465/13 "2001-08-01T15:45:42Z")
As mentioned previously, Occam’s razor is commonly used as a sort of algorithm for choosing between multiple decisions/ideas. It has nothing to do with truth per se, though one can extend it to do so by also postulating that the universe’s laws are selectable by occam’s razor. The difference between the two positions is not minor. For a good discussion of truth (bad **kabbes** for not linking the thread he threadspotted ;)) [check this thread](http://boards.straightdope.com/sdmb/showthread.php?threadid=49819). I certainly learned a few things in it, but be prepared to set aside a good few days to wade through the whole thing. 😃 ---
**Author:** ![AHunter3](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/ahunter3/32/368_2.png) [@AHunter3](https://boards.straightdope.com/u/AHunter3)\ **Post date:** [August 1, 2001, 9:00pm UTC](https://boards.straightdope.com/t/occams-razor-self-referential/74465/14 "2001-08-01T21:00:16Z")
Originally posted by Whack-a-Mole: > [@](#): > > By your examples the 5th century farmer would indeed be correct in applying Occam’s Razor and saying the sun revolves around the earth. He’d be wrong, of course, but as far as anyone knew at that point it was true and seemed to make the most sense. However, it does not take someone intentionally exploring more complex explanations to arrive at the right answer. > What in fact happened was people started looking at the stars and planets and tracked their movements. When it came to other planets’ movement across the sky they saw some very weird behavior. … > Eventually, some bright guy figured out if you had the earth orbiting around the sun then you got back to the simplest answer that fit the observations (Occam’s Razor). Yes, but in order to get the 5th century farmer to acknowledge this, you first have to get past the initial mindset. You’re realing with a farmer who considers it to be self-evident that the sun circles a stationary earth. You may be able to get the farmer to consider the importance of the astronomical observations that reconcile easily only with a heliocentric model–then again, the farmer may be uninclined to listen, especially if he gets wind of the fact that you are leading up to the conclusion that the earth goes around the sun. And that’s what I was referring to when I said > [@](#): > > only if the person weilding the blade is willing to continue considering the more complicated explanation long enough to examine them fairly. ---
**Author:** ![Patty\_O\_Furniture](https://avatars.discourse-cdn.com/v4/letter/p/96bed5/32.png) [@Patty\_O\_Furniture](https://boards.straightdope.com/u/Patty_O_Furniture)\ **Post date:** [August 2, 2001, 2:16am UTC](https://boards.straightdope.com/t/occams-razor-self-referential/74465/15 "2001-08-02T02:16:08Z")
Isn’t **Occam’s Razor** just a more eloquent way of stating probability? In other words, the probability of a single (or simple) event happening is _always_ more likely than that of two (or complex) events happening. “I will get heads when I flip this coin” is always more probable than “I will get heads when I flip this coin _and_ draw a Jack from that deck of cards”. So if something can be explained using fewer or simpler steps, it’s simply more probable. No? ---
**Author:** ![ultrafilter](https://avatars.discourse-cdn.com/v4/letter/u/3d9bf3/32.png) [@ultrafilter](https://boards.straightdope.com/u/ultrafilter)\ **Post date:** [August 2, 2001, 3:20am UTC](https://boards.straightdope.com/t/occams-razor-self-referential/74465/16 "2001-08-02T03:20:54Z")
> [@](#): > > \*Originally posted by Attrayant \* > \*\*Isn’t **Occam’s Razor** just a more eloquent way of stating probability? In other words, the probability of a single (or simple) event happening is _always_ more likely than that of two (or complex) events happening. > > “I will get heads when I flip this coin” is always more probable than “I will get heads when I flip this coin _and_ draw a Jack from that deck of cards”. > > So if something can be explained using fewer or simpler steps, it’s simply more probable. > > No? \*\* I agree with what you said, but your example might be off, due to an ambiguity in the language. If you mean “I will get heads on this coin given that I’ve already drawn a Jack”, then the events are equiprobable. If you mean “I will get heads and draw a Jack”, then you’re absolutely right. Of course, **I** know that you meant it in the second sense (;)), but I thought I’d clarify for others. ---
**Author:** ![Phobos](https://avatars.discourse-cdn.com/v4/letter/p/3d9bf3/32.png) [@Phobos](https://boards.straightdope.com/u/Phobos)\ **Post date:** [August 3, 2001, 1:22pm UTC](https://boards.straightdope.com/t/occams-razor-self-referential/74465/17 "2001-08-03T13:22:33Z")
My impression is that Occam’s Razor is just a rule of thumb that keeps people from jumping to unsubstantiated conclusions. It is not a specific step of the scientific method. ---
**Author:** ![MeCorva](https://avatars.discourse-cdn.com/v4/letter/m/d9b06d/32.png) [@MeCorva](https://boards.straightdope.com/u/MeCorva)\ **Post date:** [August 7, 2001, 4:18pm UTC](https://boards.straightdope.com/t/occams-razor-self-referential/74465/18 "2001-08-07T16:18:51Z")
Well, I’ve always been at best uneasy about Occam’s Razor, but it sounds like everyone else is too. I mean, it is clearly possible to make scenarios where it doesn’t work --but in general, it still feels like common sense. Grrr. However, in some senses, the Occam’s Razor is the basis for surviving in this world. I mean, it’s possible that my best friend is actually an alien masqurading perfectly as a human, and will, tommorrow, destroy the planet, and had I just known, I could kill him now… but, I doubt it. Maybe I’ll wake up tommorrow only to find out that gravity _HAS_ reversed itself, but I’m not selling my shares now. Essentially, at it’s core, it is a statement that says “Things will remain how they always were, unless something different happens”, and, yeah, I tentatively agree with that. Me’Corva ---
**Author:** ![Spiritus\_Mundi](https://avatars.discourse-cdn.com/v4/letter/s/c68b51/32.png) [@Spiritus\_Mundi](https://boards.straightdope.com/u/Spiritus_Mundi)\ **Post date:** [August 7, 2001, 7:34pm UTC](https://boards.straightdope.com/t/occams-razor-self-referential/74465/19 "2001-08-07T19:34:14Z")
**kabbes** has already said it. _Occam’s Razor_ is an axiomatic procedure used to decide between alternative explanations which account for the same phenomenological effects. The reason that Newtonian physics gave way to relativistic physics is not that _Occam’s Razor_ was being applied from a different perspective, it is that Newtonian physics ceased to account for the observered phenomena. _Occam’s Razor_ (Or **Ye Olde Law of Parsimony** ) is not, strictly speaking, a statement of probability. We have no way of meaningfully assigning probabilities to the options being discussed, and if we could then we would have to rephrase old William: _70% of the time it is vain to do with more that can be done with less; 16% of the time it is vain to do with less what can be done with more; 14% of the time it is vain to get out of bed in the morning._ ---
**Author:** ![Dave\_Stewart](https://avatars.discourse-cdn.com/v4/letter/d/e274bd/32.png) [@Dave\_Stewart](https://boards.straightdope.com/u/Dave_Stewart)\ **Post date:** [August 8, 2001, 6:47am UTC](https://boards.straightdope.com/t/occams-razor-self-referential/74465/20 "2001-08-08T06:47:38Z")
How does Occam’s Razor jibe with chaos theory? Turbulence can’t be predicted. That’s the nature of it. Like Einsteinian physics, it goes beyond simple cause and effect. Is this what AHunter3 is saying? [Next page](https://boards.straightdope.com/t/occams-razor-self-referential/74465.md?page=2)