Is Occam's Razor Obsolete in Light of Modern Scientific Complexity?

[Ivan Seeking]

First, we find in the skeptics dictionary that the concept is not well defined.

The original principle seems to have been invoked within the context of a belief in the notion that perfection is simplicity itself. This seems to be a metaphysical bias which we share with the medievals and the ancient Greeks. For, like them, most of our disputes are not about this principle but about what counts as necessary. To the materialist, dualists multiply pluralities unnecessarily. To the dualist, positing a mind as well as a body, is necessary. To atheists, positing God and a supernatural realm is to posit pluralities unnecessarily. To the theist, positing God is necessary. And so on. To von Daniken, perhaps, the facts make it necessary to posit extraterrestrials. To others, these aliens are unnecessary pluralities. In the end, maybe Occam's razor says little more than that for atheists God is unnecessary but for theists that is not true. If so, the principle is not very useful. On the other hand, if Occam's razor means that when confronted with two explanations, an implausible one and a probable one, a rational person should select the probable one, then the principle seems unnecessary because so obvious. But if the principle is truly a minimalist principle, then it seems to imply the more reductionism the better. If so, then the principle of parsimony might better have been called Occam's Chainsaw, for its main use seems to be for clear-cutting ontology.

http://skepdic.com/occam.html

Next, the concept predates modern physics and is no more valid than 12th century physics.
Consider Occam's original premise:

The original principle seems to have been invoked within the context of a belief in the notion that perfection is simplicity itself

Clearly the credibility of this premise died with QM.

Anyone who understands QM hasn’t studied it long enough

------ RP Feynman

Not only is this concept ill defined and out of date, it is often used as a scientific principle – like F = ma – when it fact it is a philosophical concept; not a scientific law. The use of this concept to rule out a competing theory is only valid to the extent that it is obvious; and without need of the long dead Occam or his nasty old rusty razor. The application of this principle in any practical matter is pseudoscience.

 

[selfAdjoint]

I've always thought of OR as a proposed search strategy; don't take up the complex explanations until you have ruled out the simple ones. It surely is not constrained by whatever you happen to be talking about. The notion that it is invalidated by QM strikes me as a nonsequitur, if not a category error.

 

[quartodeciman]

OR is intended to cover real choices between totally identical situations, with no other reasons for preference involved. Sure, choose the simpler alternative. But most theories are not identical, either in method or in the choice of territory to be covered. Most new theories propose to move into distinct new territories. Two other criteria are more important: fecundity (richness of results) and plausibility (soundness of deductions).

 

[Ivan Seeking]

Originally posted by selfAdjoint
I've always thought of OR as a proposed search strategy; don't take up the complex explanations until you have ruled out the simple ones.

In this form it makes perfect sense. This is not the typical language.

The notion that it is invalidated by QM strikes me as a nonsequitur, if not a category error.

I don't see any simple explanations in modern physics. All of our simple expectations failed. This is why we have to discover the laws of physics; why we can't deduce all by logic as the Greeks tried. I see no evidence that we can anticipate the correct answers with our sense of logic or simplicity. To the point that they even exist, all explanations are complex. In fact, in the end - at the deepest levels - we have no answers.

Where is the evidence that simple answers prevail?

 

[Ivan Seeking]

Originally posted by Ambitwistor
There are many versions of it; some of them are well-defined (and correspondingly limited in scope), e.g.:

http://quasar.as.utexas.edu/papers/ockham.pdf

Occam's razor, in this view, is a quantitative codification of how people consistently associate beliefs with evidence.

Used by who? Scientists know that you can't disprove a theory on the basis of Occam's razor. You can, however, ignore a theory on that basis, if you choose.

This assumes all things being equal; in the real world they never are.

Well, what are you arguing about? Occam was stating the obvious, after all.

Occam was really making a religious statement; after all.

Nonsense. It is not "pseudoscience" to choose which of two theories you want to pursue, on the basis of "simplicity" or any other basis, so long as both theories are scientific and not falsified.

Personal choices about research are one thing; dismissing all by way of Occam is another. This is the typical mentality expressed by many students and graduates in the sciences: Explanation A is simpler than B, therefore A must be the correct answer.

I see this usage as utter garbage. In my experience, in the real world the correct explanation is almost never the simple one.

 

[Ivan Seeking]

Originally posted by Ambitwistor
You don't have to assume "all things equal" to apply Occam's razor.

So we should apply OR when faced with evidence for a more complex hypothesis?


[quoteRegardless of what Occam's intent was, his principle is still applicable.[/quote]

Only to the extent that it is not needed.

Tell me: I have a set of 100 data points that look like a line, except there is a little bit of scatter. I want to fit a curve to it. Do I fit a line, or do I fit a 100th-degree polynomial to it with 100 coefficients? The latter can pass exactly through every data point with no error. Which theory should be preferred: the linear theory or the 100th-degree polynomial theory?

Only to the extent that it is not needed.

Sorry, Ivan, but you do not speak for scientists.

I speak from my own experience...so you speak for all scientists?

Yes, scientists do dismiss overly complicated theories when simpler alternatives exist, on the basis of Occam's Razor.

Overly complicated; when exactly does the "overly" kick in?

But that is not because the simpler theory "must be the correct answer".

I'm glad we agree.

The point is that we should not assume more than we have evidence for. If we have many competing theories, all of which explain the data, then the data cannot decide between them. But unless you have a specific reason to prefer one particular theory over any of the others, one should put the greatest degree of belief in the theory that has the fewest free parameters.

Boloney. They should each be considered on their own merit.

I can make up an arbitrarily complex theory to account for any data, but that doesn't mean it's a good theory. Like I said, you can come up with a theory that will explain any finite set of data exactly, by making it complicated enough, but it has no predictive power. It's like epicycles, compared to Kepler's laws.

Like classical physics compared to QM?

 

[selfAdjoint]

As a search strategy OR is useful, but in general a lot has been learned in the last few decades about searching, depth first versus breadth first, the use of frustrated systems modeled on spin glasses, etc. What I would like to see is the search strategy google uses!

 

[Ivan Seeking]

Originally posted by Ambitwistor
We should apply it at all times. For a more complex hypotheses to be more plausible than a simpler one, it has to fit the data considerably better than the simpler hypothesis. If there is enough evidence in favor of the more complex hypothesis, then it will win out.

How much is considerably? More plausible? Why needlessly rule out potentially viable options? This only increases the chance of following the wrong path ad infintum.

Both hypothesis are consistent with all of the evidence, after all, but one of them is simpler than the other.

This is silliness! You assert that it is just as likely that I lost my keys as it is that aliens took them; but the alien theory is just more complicated? This is not an example of OR; it's statistics.

Better than you do, if you are going to maintain your ridiculous strawman position that scientists think that Occam's Razor is capable of proving or disproving theories.

Ah, you're psychic also? I maintain that beyond the obvious, it has no place in science. I think the history of scientific advances supports this notion.

That depends on one's judgement, of course, which is why there are arguments among scientists about what theories to prefer. In more restricted cases, it is possible to make "overly" a quantitatively precise concept; that was the point of the article I linked.

It is still arbitrary.

They are considered on their own merit, and the simpler theory has more merit in the absence of evidence favoring the more complex theory. That's the whole point of science, after all. Otherwise we'd be fitting all our data with Nth-degree polynomials instead of coming up with predictive theories.

"in the absence of evidence favoring the more complex theory"
Not the usage that I see. This also disagrees with your first statement in this post.

If you had proposed quantum mechanical laws in the 17th century, you would have been laughed at, and rightly so: there was no evidence that supported such a hypothesis over Newton's laws. You could equally well have proposed many other more complicated alternatives to Newton's laws, which would have been completely unsupported by the data as well. There are always infinitely many laws you can propose to replace existing laws: one of them may be right, but infinitely many others will be wrong. Without evidence, there is no way to pick one over the other, so the simplest theory is the most credible, on the basis of the evidence that exists at the time

The point is that consistently we see physics increases in complexity; it does not decrease. This is in direct opposition to the implicit logic of OR. We should expect more complex solutions; not simpler ones.

Edit: If you chose to use only a limited interpretation OR, one that is really the principle of pasimony in the strictest sense, then really we agree. This is not how this principle is interpreted by many educated people; nor is this interpretation the motivation for this thread. If this were the only interpretation we would be done.

the principle that entities should not be multiplied needlessly; the simplest of two competing theories is to be preferred

Really this reads like the 2nd ammendment to the constitution: I agree with the first point but not the second. The simplest and the more complex should be considered on their own merit.

How would you define the word preferred in this context?

 

[Ivan Seeking]

Originally posted by selfAdjoint
As a search strategy OR is useful, but in general a lot has been learned in the last few decades about searching, depth first versus breadth first, the use of frustrated systems modeled on spin glasses, etc. What I would like to see is the search strategy google uses!

Perhaps we will finally obtain a TOE using random searches in super computers. Hmmmm, that would be disappointing somehow... Will the next Einstein be a Quantum Computer?

 

[Ivan Seeking]

I got busy. I'll be back.

 

[Ivan Seeking]

Originally posted by Ambitwistor
Ivan, you obviously are not a practicing scientist. There are infinitely many potentially viable options, and not that many scientists working on any specific problem. Every once in a while someone will bring up a complicated theory that was previously ignored because it was more complicated --- even today, people discussion aether theories and variable-light speed theories as alternatives to relativity, for instance --- but it is simply not possible to spend time on all "potentially viable options", nor is it reasonable to prefer more complicated theories when simpler ones work just as well.

First, I am only a graduate in physics with a 30 year habit [what I do here at PF is mostly not included in that statement]. I do practice science at times as a function of my work and personal interests. Between my degree and my long experience with physics through books, lectures, and formal discussions, I have invested perhaps forty thousand hours into the subject. Clearly I do not qualify as a mainstream research scientist, however considering my degree and my long history with the discipline, I can hardly be considered an outsider.

by Ivan
If you chose to use only a limited interpretation OR, one that is really the principle of parsimony in the strictest sense, then really we agree. This is not how this principle is interpreted by many educated people; nor is this interpretation the motivation for this thread. If this were the only interpretation we would be done.

by Ambitwistor
All right, then, I think we do agree. Even Occam himself agrees: if you read how he phrased the statement (or at least, the phrasing that is attributed to him), he said "ideas should not be multiplied beyond necessity". He didn't say anything like what you are claiming. Whether some people do claim what you say is another matter, but in my experience scientists do use Occam's razor as a principle of parsimony.

Well, you know where I have spent my time lately. I see this concept used improperly by science and engineering students, and graduates [at least] on a fairly regular basis.

For instance, Lorentz's aether theory is exactly equivalent to Einstein's special relativity in every measurable way. If you ask a relativist why he doesn't consider LET over SR, he won't say that it's because LET is wrong. He will say that Lorentz's aether is unobservable, and SR can do everything that LET can do without an extra untestable aether lying around, so he takes the simpler theory.

If all my discussion were with you this thread would likely not exist.

But what does that mean, "should be considered on their own merit"? Even if you assign equal prior belief in the linear theory and the 100th-degree-polynomial theory, in my previous example, after seeing the data are you really going to believe the two are equally plausible explanations?

I mean that rather than use words like “belief”, I prefer to consider things strictly in terms of probabilities. I may comment on your paper later. It is most interesting.

There is still the deeper objection to Occam’s motivation. The original thesis that motivates OR - the religious belief that simplicity is perfection, and since the universe was made by God, it must be simple – appears to be incorrect. You pointed out that physics reduces complexity with simpler models. My objection is that nature keeps forcing more complex models; physics only responds to this requirement. So at its core, the belief in ultimate simplicity appears to be contraindicated by modern physics. For this reason, I argue that in the face of the evidence, the core philosophy of OR is statistically unlikely.

 

[Ivan Seeking]

Originally posted by Ambitwistor
To someone who subscribes to the Bayesian interpretation of probability theory, as I do, a probability is a degree of belief. Janyes's book Probability Theory: The Logic of Science has a good discussion of this perspective.

If you choose this as a definition, fair enough.

Occam's motivation and the validity of Occam's razor are independent issues; I'm not too interested in debating the former.

I think the implicit philosophy does matter. This is clearly what motivates many common interpretations of this concept. Also, this is a philosophy forum. I didn't post this in mathematics or physics for a reason.

Well, then we appear to disagree on whether models get simpler or more complex.

You seem to have the wrong idea. If we consider that modern physics began with Newton, clearly we have seen a tremendous increase in the complexity of the physical models required to describe that observed. The latest data point to add complexity to the curve appears to be dark energy.

Occam's razor doesn't state that the simplest theory is right. It states that we should place the most belief in the simplest theory consistent with the evidence, in the absence of any evidence favoring the more complicated theories. I would still like to see you address the question of why you wouldn't prefer a 100th-degree polynomial fit instead of a linear fit, since it's "statistically unlikely" that the linear theory is right.

As I said, in my first post:

The use of this concept to rule out a competing theory is only valid to the extent that it is obvious

I have never disputed this point. Why do you keep ignoring this?

 

[Ivan Seeking]

Originally posted by Ambitwistor
Many common interpretations of Occam's Razor are based on Occam's theological motivations?? I doubt that!

On a superficial level, no. But at the deepest level, any belief based premise, such as the more general notion taken from OR that we should expect simplicity in nature is ultimately theological in nature. Physicist do practice philosophy daily. It is argued that this is often not unrecognized. Here is a link to an article that discusses this notion. I have posted this in the past but it has been a while.

http://physicsweb.org/article/world/15/4/2/1#2

We see complexity go up and down. When more phenomena are discovered, more complex models tend to be proposed, but then people find a way of fitting these proposals into an elegant framework and the models get simpler again.

A macroscopic view - the complete history of physics - yields a more and more complex curve...thus far. How many dimensions do we work with now? Up to twelve? I think your Newtonian line in three dimensions has morphed into a hypervolume.

You seem to be ignoring my response to your point, which is that all uses of Occam's Razor are obvious.

I don't agree. Please see the link in the first post.

There is a philosophy implicit in a thousand decisions a day. The article linked above describes the basis for this premise. This however is another discussion altogether.

Again, this is a philosophical discussion. A rigorous mathematical treatment such as the one posted by you may or may not have anything to do with the premise my argument.

 

[NateTG]

Occam's Razor:
If there are two theories that make the same prediction, then the simpler theory is better.

So, for example, according to OR, on classical physics scales - i.e. non-relativistic/non-quantum masses and speeds - classical physicis is the best theory.

When you are dealing with domains where the theories differ, then you use the theory that is more consistent with your experimental data. (OR does not apply here.)

So let's take a look at the example of lost keys:

Theory 1: I lost my keys
Theory 2: Space aliens stole my keys.

Theory 1 makes the prediction that my keys will turn up somewhere that I've been.
Theory 2 makes the prediction that there were aliens near me, so the aliens should have been observable.

Clearly experience (for most people) is not consistent with theory 2. That eliminates theory 2 before OR really comes into play.

There are several problems with the application of OR in general -- the notions of theory, the same, and better are not rigorously stated, and it is entirely concievable that a theory can trade conceptual simplicity for computational complexity. An example of this might be the standard model (a catalog of particles and interactions) vs. string theory (conceptually elegant, computationally painfull).

A good example of Occam's Razor being applied is the history of the motion of the planets: Although Keppler's work is equivalent on the motion of the planets, it's usually not covered in favor of Newton's equations because Newton's equations are simpler, and make the same predictions.

 

[Ivan Seeking]

Originally posted by Ambitwistor
This is nonsense. Belief is not theology, nor is probability theory or logic.

Belief is always faith based. Where do we define faith in science? Faith is for the religious.

So? Nobody is denying that Occam's Razor is a philosophical principle: it can't be used to prove or disprove physical theories.

So, it applies in many more ways than as in the one paper you cite.

I don't know about you, but I work with the same four that Newton did.

Now you are either being ridiculous or you don't know nearly as much as I had assumed.

 

[Ivan Seeking]

Originally posted by NateTG
Occam's Razor:
If there are two theories that make the same prediction, then the simpler theory is better.

So, for example, according to OR, on classical physics scales - i.e. non-relativistic/non-quantum masses and speeds - classical physicis is the best theory.

When you are dealing with domains where the theories differ, then you use the theory that is more consistent with your experimental data. (OR does not apply here.)

So let's take a look at the example of lost keys:

Theory 1: I lost my keys
Theory 2: Space aliens stole my keys.

Theory 1 makes the prediction that my keys will turn up somewhere that I've been.
Theory 2 makes the prediction that there were aliens near me, so the aliens should have been observable.

Clearly experience (for most people) is not consistent with theory 2. That eliminates theory 2 before OR really comes into play.

thank you.

There are several problems with the application of OR in general -- the notions of theory, the same, and better are not rigorously stated, and it is entirely concievable that a theory can trade conceptual simplicity for computational complexity. An example of this might be the standard model (a catalog of particles and interactions) vs. string theory (conceptually elegant, computationally painfull).

A good example of Occam's Razor being applied is the history of the motion of the planets: Although Keppler's work is equivalent on the motion of the planets, it's usually not covered in favor of Newton's equations because Newton's equations are simpler, and make the same predictions.

How would you characterize the case of the old wave-particle paradox?

 

[NateTG]

Originally posted by Ivan Seeking
How would you characterize the case of the old wave-particle duality paradox?

I would say that there were two theories - light as particle and light as wave and that the theories make different predictions in some situations. When there are theories that make different predictions, the appropriate approach is to experiment (use the razor to shave).

I don't personally know enough of the history/theory to have a whole lot of insight.

 

[NateTG]

Originally posted by Ambitwistor
I said they were invisible space aliens, and you haven't found your keys yet. The evidence --- namely, that you can't find your keys --- is equally consistent with both theories. If you find your keys nearby, then I agree that theory 1 is preferred by the evidence alone. (Unless I postulate that the invisible space aliens also like to secretly return keys somewhere nearby.)

And I said observed not seen. The aliens might still be smellable, hearable, or touchable.

If you have a situation where there is no opportunity for experimentation then theory is pointless.

 

[Ivan Seeking]

Originally posted by Ambitwistor
Hardly. I can believe something, knowing full well that I might be wrong, without "taking it on faith".

A belief is an internal thought or memory which exists in one's mind. Most people accept that for a belief to be knowledge it must be, at least, true and justified. The Gettier problem in philosophy is the question of whether there are any other requirements before a belief can be accepted as knowledge.

http://en.wikipedia.org/wiki/Propositional_knowledge

So typically belief does imply an intellectual choice beyond mere probabilies. At the least, in the common usage belief cannotes extreme bias. You have selected an obscure and rigorous defintion of belief; this does not apply to everyone.

So, you're ignoring the original point, which is that Occam's theology has nothing to with how Occam's Razor is commonly intepreted. I would wager that most people don't even know anything about Occam other than the statement of his Razor --- and many of those who say they are applying Occam's Razor probably don't even know his original wording.

There are at least two parts to OR:

First, "plurality should not be posited without necessity."
No objections.

A Popular usage: "The simplest explanation tends to be the correct explanation".
If you never see this interpretation, then no wonder we don't agree.

Earlier you said: "but it is simply not possible to spend time on all "potentially viable options", nor is it reasonable to prefer more complicated theories when simpler ones work just as well."

My point is that evidence is often rejected or ignored because it represents challenges to the simple explanations. This results from belief based bias.

If you are implying that Newton didn't use three space and one time dimension in his theories, you're mistaken. It's just that space and time were absolute in Newton's theory, whereas they were unified and relative in Einstein's.

Are you arguing that the whole of modern physics is no more complex than 17th century physics? 18th century? 19th Century?

Also, you are clearly familiar with String Theory. Why do you seem to evade my reference to the 10 or 12 dimensions that appear to be required to explain all forces in nature?

 

[Ivan Seeking]

Originally posted by Ambitwistor
This is certainly not true. I can believe it will rain tomorrow without being anywhere even close to certain that it will rain tomorrow, or "accepting it on faith"./quote]

Aside from your mathematical reference, what then is the difference between belief and expectations?

Moreover, whether I define a probability to be a degree of belief is independent of the question of whether "belief" is the same as "faith".

I understand; and this is a very reasonable approach.

The interpretation I use is that one should put greater belief in the simpler theory, in the absence of any evidence favoring the more complex theory.

Again, this comes down to our personal exposure to this question.

[quoteReally? "Often"? Says who?

I see this frequently. Perhaps you don't see this because you don't explore the fringe.

I'm arguing that in the history of scientific development, there is not a universal replacement of simpler theories with more complicated ones. Sometimes theories get more complicated, and sometimes they get simpler.

Still, complexity does increase. Based on the evidence, we should drive for the simplest theory, and we should expect more complexity.

This also speaks to the assumption that a TOE can even exist. This assumption in itself reflects the philosophy of William of Ockham.

I'm not "evading" your reference, I'm ignoring it. String theory says that 10 or 11 dimensions are needed to describe nature, but that doesn't mean that I agree with that claim. We really have no idea of whether extra dimensions either exist or are necessary to explain anything.

That fine. So you ignored a legitimate reference to a, or the leading contender for a unified theory becuase you don't know if its neccesary.

But, for that matter, as I said earlier and you ignored, a string theorist would claim that string theory, even with extra spacetime dimensions, is fundamentally simpler than the existing Standard Model. That's why string theorists like string theory. [/B]

True. The fact remains that to the best of our knowledtge, the universe is not simple and we should not expect it to be. The significance of this implicit philosophy, one that is counter to that of the philosophy OR, is discussed in the Physics Web Link.

 

[Ivan Seeking]

There are many reasons why fringe claims are often ignored, but I don't think Occam's Razor is necessarily one of them.

I didn't say claims, I said evidence.

Otherwise, I guess I have made my argument.

I think an important distinction has not yet been made in this thread: a theory might be simple, but its solutions might be arbitrarily complex.

This is an interesting point. Could you elaborate?

 

[Mentat]

Originally posted by Ivan Seeking
Belief is always faith based.

I heartily disagree with your take on OR, Ivan (no offense), but will explain my disagreement on another post. This one is directed at the quoted sentence. You see, this is actually not true. Belief can be based on credulity, or it can be based on faith, or it can be without basis at all.

"Faith is the assured expectation of things hoped for, the evident demonstration of realities, though not beheld" [Italics mine] Hebrews 11:1, New World Translation of the Holy Scriptures. It's the best definition I've heard so far .

Thus the difference between faith and mere belief is established.

 

[Mentat]

IMO, Occam's Razor has not been properly defined here yet.

You see, Occam's Razor is not "When two hypotheses dictate the same thing, but one makes less assumptions than the other, that one is better", it is "When two hypotheses dictate the same thing, to the same level of accuracy and tenability, the one with less assumptions is better".

You mentioned QM, right. Well, QM needs to make more assumptions than Newtonian Mechanics would, if applied to the microscopic scale, doesn't it (so it seems that Occam's Razor would have failed here, right?)? However, QM is more accurate, and thus better by default.

 

[Ivan Seeking]

Originally posted by Mentat
IMO, Occam's Razor has not been properly defined here yet.

You see, Occam's Razor is not "When two hypotheses dictate the same thing, but one makes less assumptions than the other, that one is better", it is "When two hypotheses dictate the same thing, to the same level of accuracy and tenability, the one with less assumptions is better".

You mentioned QM, right. Well, QM needs to make more assumptions than Newtonian Mechanics would, if applied to the microscopic scale, doesn't it (so it seems that Occam's Razor would have failed here, right?)? However, QM is more accurate, and thus better by default.

The real point of this comparison is not that QM was less appropriate for describing the behavior of the very small than was Newtonian Mechanics, I was pointing to the continuing need for more complex descriptions of reality. Again, this and the fact that we do mostly assume and expect that a TOE can exist are somewhat of a dichotomy. The link here is not the explicit application of parsimony; it is the overall philosophy of William that we still see today. Obviously part of the reason that we expect a TOE is the elegance observed in nature through physics, so I don't mean to argue that such expectations are without merit, but that nature can be reduced to a finite set of equations is assumed without proof.

This seems to be one of the most basic assumptions of physics.

 

[Ivan Seeking]

Originally posted by Ambitwistor
I don't think it's the case that contradictory evidence is ignored, if that evidence is well-established. If it's on the edge of measurement, maybe. More rigorous evidence is required to cast doubt upon a well-established theory, after all. This can also be phrased rigorously in the language of probability theory.

Well, I didn't want to start a UFO discussion here, but I must, so I will tackle it this way. From what I have seen of RADAR data that corroborates multiple eyewitness testimony, some kind of unknown atmospheric phenomenon [at least] is seen and interferes with aircraft. Since this gets labeled UFO [ =ET ] a truly fascinating subject is generally ignored. The debunkers typically pull out Occam's Razor to discredit the entire event by way of the ET hypothesis. The assumption typically made is that this must be ET so it can't be real; so ignore the whole subject. I see similar thinking applied in most fringe subjects. So we don’t see Occam used to judge competing theories, we see it used discredit or ignore eyewitnesses, in addition to RADAR data and other evidence. The simplest explanation is always that the whole thing is a hoax; no matter how compelling the evidence.

 

[Mentat]

Originally posted by Ivan Seeking
The real point of this comparison is not that QM was less appropriate for describing the behavior of the very small than was Newtonian Mechanics, I was pointing to the continuing need for more complex descriptions of reality. Again, this and the fact that we do mostly assume and expect that a TOE can exist are somewhat of a dichotomy. The link here is not the explicit application of parsimony; it is the overall philosophy of William that we still see today. Obviously part of the reason that we expect a TOE is the elegance observed in nature through physics, so I don't mean to argue that such expectations are without merit, but that nature can be reduced to a finite set of equations is assumed without proof.

This seems to be one of the most basic assumptions of physics.

But wha thas it to do with Occam's Razor?

 

[Ivan Seeking]

Originally posted by Mentat
But wha thas it to do with Occam's Razor?

I assume that you stick with the strictest interpretation. As I said in the beginning, the interpretations of OR can run wild. I think the philosophical motivations for OR permeates the thinking of most people more than we generally realize. Again, the most general embedded philosophy here is that we should expect simplicity from nature. The linked article discusses how philosophy does play an active role in the scienctific process.

 

[Ivan Seeking]

Originally posted by Ambitwistor
I don't really believe that anybody "typically" uses this argument. There have been plenty of weird "UFO" phenomena that were later found to have natural explanations, and educated debunkers know this. If I hear about some unexplained event in the sky, I certainly don't assume that it must be a hoax. I do assume that it probably has a non-ET explanation.

I can only tell you what I hear and see.

Moreover, assuming that "this must be ET so it can't be real" is not an application of Occam's Razor. It's not even an application of logic: "It must be ET. It can't be ET. Therefore it's not real." doesn't make any logical sense.

From what I see, the problem is not the stories that can be explained, those are easy to deal with, it's the credible stories that can't be explained. Since we have no convienent explanations, the default explanation becomes ET - which of course is much less likely to be the explanation than a hoax. Therefore its a hoax. In other words, manipulate the argument so that we can wrongly apply OR.

That's ridiculous. Conspiracy theorists are usually ignored precisely because deception is usually not the simplest explanation.

I never said anything about conspiracies. ?

Sometimes the hoax hypothesis is the simplest explanation consistent with the evidence, and sometimes it's not: it depends on what the alternate explanations are, and what the evidence is. [/B]

The problems come when we have no viable alternative explantion.

 

[Ivan Seeking]

Originally posted by Ambitwistor
Then, it is not an assumption of physics. We'd come up with the same laws regardless of whether we believe there are finitely more or infinitely more laws yet to be discovered, because the goal is always to explain as much as we can: if we find a set of laws that happens to describe everything we can observe, then we don't have to assume that the set of laws is finite or infinite to do that. And supposing we do construct a set of self-consistent laws (TOE or not) that describe everything we observe. That still doesn't prove, and never can prove, that those are all the laws that exist. An assumption that there are a finite number of laws is just irrelevant to the process of physics.

True. We can always assume processes exist that we never observe; so there could be physical laws veiled forever from our view. However, today we find that a great disconnect exists between two highly successful theories - GR and QM. Unification of these two theories is considered the holy grail of modern physics. As an example of my argument, with one exception - my favorite college physics professor - I have never heard anyone suggest that unification may not ever be possible. I have surely never heard a discussion on why unification fundamentally may not be possible. Of course, if M theory ever leaps from the realm of philosophy to that of physics by way of testable predictions, I admit that my point could be moot.

 

[Ivan Seeking]

Originally posted by Ambitwistor
If we have no viable alternative explanation to a hoax, then by definition, a hoax is the best explanation that we have. What is the problem?

Exactly! You just did what I am claiming.

How about considering that we don't know all of the potential explanations? This is another option that gets ignored. This exactly is where I see that science goes blind. This is why so many people like me find this so frustrating. We are convinced that something vert strange is afoot, but we can't imagine what.

 

[Ivan Seeking]

Originally posted by Ambitwistor
there is no a priori reason to believe that unification must be possible.

That makes two.

 

[Ivan Seeking]

Originally posted by Ambitwistor
Utter nonsense. Science does not ignore the possibility of unknown explanations. If it did, then science wouldn't exist at all.

I just gave an example of where this does often happen. Though in fairness, there are a few scientists willing to throw their careers to the wind and pursue unpopular subjects.

Occam's Razor applies to explanations that you do have; it can't be applied to explanations that you don't have, because you can't say anything about either how simple they are, or how well they fit the evidence.

However it can be used wrongly to defer further investigation. In short, it is used to rule out unknown explanations.

 

[Ivan Seeking]

Originally posted by Ambitwistor
Ivan, in a field where hoaxes and mundane natural and man-made phenomena have often proven to be correct explanations, hoaxes and mundane natural and man-made phenomena are rightly a good assumption.

Approximately 90-95% of all sightings. True.

There simply isn't the funding to go chasing after every weird thing that some guy claimed he saw in the sky, considering how often people have studied UFO phenomena in the past and turned up no amazing new phenomena.

Again, the cases that interest me do not depend on what "some guy claimed he saw in the sky". Next, only after many years of refusals has the journal Nature agreed [in principle at least] to publish well penned papers on the subject. Funding is not the only issue.

Unknown explanations are never "ruled out", certainly not by Occam's Razor. Unknown explanations may not be actively pursued because nobody is interested, in a field that historically has not proven a fruitful source of interesting new phenomena. [/B]

I think you've hit the nail on the head. The trouble is, no one is smart enough to come up with anything the rival the ET hypothesis. So, since nature abhors a vacuum, we get Art Bell.

 

[Iacchus32]

That which is most obvious -- and hence, easiest to deduce -- is usually that which is most prevalent. Whereas that which is most prevalent, is usually the "status quo."

Hence it would seem, Occam's Razor is quite often "a ploy" to maintain the status quo.

 

[geometer]

I have quickly skimmed the posts here, so I apologize in advance if I am restating something or missing the whole point here. I remember reading somewhere Occam's actual words which were: "Construct no unnecessary hypotheses." Our interpretation of this as "All things being equal, the simplest explanation is probably the right one" is an interpretation of this statement or maybe a corollary.

 

[vanesch]

I don't see any simple explanations in modern physics. All of our simple expectations failed.

One shouldn't confuse "simple" with "simplistic" or "naive". The first one refers to the use of only a few, even if very abstract and counter intuitive, concepts. Modern physics strives towards it, with success. The latter means: what I can find without much thinking.
Unification is the typical example in physics, and has already worked out with success several times. Take electricity and magnetism. Before Maxwell, there were several, apparently unrelated, different, but indeed simplistic, explanations of several phenomena: static electricity, currents, magnetic needles etc...
Maxwell 4 equations, using 2 vector fields, describing ALL those phenomena at once. Although conceptually harder to understand, LESS concepts were used, in a more abstract way. This is what "simple" means in physics. A bit later, it was possible to reformulate, in relativistic language, the same mathematical content, but using ONE SINGLE entity, the 4-potential, and 1 equation. Again, things became less obvious and more abstract, but with less different concepts: simplicity again.
This story went on and on, for most of the 20th century.

Simpler, and at the same time more abstract and difficult. But simpler, because of a lower number of different concepts.

cheers,
Patrick.