Fake Explanations

Well, one difference between "heat conduction" and "phlogiston" is that the former carries some additional information with it - heat conduction is a well-understood mechanism by which energy is transferred from place to place. Maybe it does apply in that situation and maybe it doesn't - in the example given, it doesn't, there's no heat-conduction mechanism to transfer heat from one side to the other - but the fact that there's actually a mechanism behind the words separates it, qualitatively, from an explanation like "phlogiston." It has equations behind it which can then be written down and tested for agreement with reality.

Really, I can quite understand the students... if you say "I don't know" you have a zero percent chance of getting the explanation right. If you say "that seems impossible," then you're guaranteed to get it 100% wrong - since it DID happen, and thus it must be possible. The best course of action in the situation is to think of all the hypotheses you can, and then guess at one of them - whichever one has the highest chance of being right, given what they know about physics.

Now, I certainly hope that the students wouldn't think that by throwing around guesses they're "doing physics" - yes, doing physics would involve taking actual measurements, and I would hope that after taking some measurements of the block over time they would see "oh, this isn't actually at equilibrium like we had all assumed." (Alternatively, if a student took the words and wrote down an actual model of how the air currents or the different metals or the heat conduction could lead to the observations, that would also be "doing physics", though the only end result of it would be to yield a mathematical model which would quickly be easy to proven false by measurements or stability analysis.) But neither of those avenues is open to them when they walk into a classroom and the teacher asks them to "explain this phenomenon."

I think the students would quite happily agree that they haven't given an explanation which is good by any sane measure - it's quite likely that many of them would also agree that they don't actually believe their explanations. But I wouldn't agree that they're being irrational in stating them.

AC, what you're describing here is a severe case of déformation educationnelle.

Really, I can quite understand the students... if you say "I don't know" you have a zero percent chance of getting the explanation right.

If you say "I don't know" you have a zero percent chance of getting a gold star in the idiot damned school system. But it is still the rational thing to say when, in fact, you don't know. You can easily do worse than maximum entropy if you guess at random.

Furthermore, "getting it right" by guessing the verbal phrase the teacher has in mind, even if the school system gives you a gold star for it, does not necessarily mean that you possess any anticipation-controllers. All you got right was a string of words, like guessing the passphrase to the teacher's login.

"Heat conduction" is a verbal phrase which may, for someone who knows the equations, invoke genuinely explanatory equations from memory. And for someone who knows the equations, it should be obvious that the equations do not predict the further side being warmer.

If you don't know the equations, then "heat conduction" is a verbal phrase invoking magic from the Star Trek genre. Even if the teacher says "You're right!", because there were only a limited number of phrases you learned about this semester and one of them had to be "right", you still don't know anything except an arbitrary passphrase.

If you memorized the equations but you didn't apply them, then "heat conduction" still invokes magic - it's not enough to know what symbols to scribble on the final exam, you've got to do the math or it doesn't count.

Dear Sir, Although your article follows the essence of logic, may I point out that Mr Spock, a personal mentor, has never had anything to do with misleading scientific explanations. Mr Spock just happens to live in the future where such things as "plasma conduits" and "warp engines" are common scientific tools. Yours truly Alexis Perrier

I agree with AC...you're being too hard on the students. I doubt very much they were stating anything with confidence. It's quite possible that some of them didn't really care about understanding physics and were just trying to get the right answer to please the teacher, but others were probably just thinking out loud. Thinking "maybe it's heat conduction" might just be the first step to thinking "no, it can't be heat conduction," or even to realizing "I don't really understand heat conduction," and there is nothing wrong with this train of thought. They were probably "biased" towards the idea that there was some physical principle causing the effect, but that was entirely rational because the professor set them up to believe that.

Great story, though.

Ed, the student's response may be due to something he needs to unlearn as discussed in the following earlier post:

http://lesswrong.com/lw/i2/two_more_things_to_unlearn_from_school/

If it's not the case, that is, if he doesn't need to unlearn anything he may still be incorrect in his understanding. In that case, this post tells one of the reasons why he may be incorrect and be aware of it.

I think this is worse compared to the behaviour addressed in the earlier post.

but that was entirely rational because the professor set them up to believe that.

They were rational, but not unbiased. They wanted to maximise their chances of pleasing the prof., not maximise their chances of understanding the world.

I think this teaching approach was great, and I might use something similar myself (there are mathematical equivalents of the above situation). Learning science means that you have to learn a boatload of facts, and learn the scientific method. Since the boatload of facts has to be accepted without question (for the whole of your early career), this undermines the teaching of the method (when it is taught at all). A few sessions like this (properly exploited by the instructor) would do a world of good.

Great post, Eliezer, and I agree with Stuart. There should be no valor in stating an uncertain guess as a certain statement -one should at least express one's level of uncertainty.

Incidentally, this is an area where legal instruction is superior to scientific instruction at the graduate/pre-thesis level.

"They wanted to maximise their chances of pleasing the prof., not maximise their chances of understanding the world."

I don't know that I buy this. If the students make a guess that's wrong, one would expect that to kickstart a process of the professor helping them to understand why it's wrong. (Student: "Um... because of heat conduction?" Teacher: "OK, what does heat conduction suggest should happen in this situation?"...) This seems more likely to result in learning than just sitting there and saying "I don't know". If anything, I think it's often a bigger problem from a learning perspective, when people are too afraid of being wrong to put out tentative ideas.

"I don't know" is a rational response to this situation if you are sure enough of your understanding of all the potential principles involved that you know they can't explain the phenomenon (and you don't happen to guess that the professor is messing with you). But it's fairly clear the students aren't in that situation, so starting to generate hypotheses about what's going on seems perfectly sensible. Of course, they should be actual hypotheses, and Eliezer's perfectly right that "because of heat conduction", if offered as an actual explanation, isn't an hypothesis as much as a cop out. But if it's a starting point, rather than an endpoint, then that seems perfectly reasonable.

In short, the problem isn't that they're guessing. It's if their guesses aren't actually saying anything, but they think that they are. (And I think Eliezer's admonition to just say "I don't know" conflates these two problems.)

Is there any way to set up a classroom (or an educational system) so that these students would get the right answer? Alternatively, is it even desirable?

If you teach students to think this way, you're saying "The world is governed by comprehensible scientific laws -- which is irrelevant, because people are constantly screwing with you." This experiment might be useful in a physics class for lawyers (who would probably catch on) or conspiracy theorists (who would, at least, have more entertaining hypotheses).

A compromise might be for the teacher to not just ask for an explanation, but ask for a testable explanation, and reward people for coming up with a theory they can falsify. The sad truth is that there's one more group that would figure out the answer right away: Creationists.

I should note that I read about this scenario in the Canonical List of Science Jokes but I have no idea whether it was a note from someone's experience. If anyone tries this, I'd love to know the result - my guess is that in real life, at least one student in the class would guess it, which is why I'd suggest having students write down their best suggestions on paper; followed by the teacher asking "How could you falsify your theory?" and writing that down as well.

Explaining things by magic has been the default state of human existence for far longer than science ever existed. Anyone using fancy words must be assumed to be invoking magic by default.

The training of a rationalist must be strict! No human can be unfair enough; you have to match swords against Nature to develop the requisite skills.

I would like to re-emphasize Eliezer's point that "I don't know" (not an uneducated guess) is the proper answer to any question where, in fact, a student (or person in general) does not know the right answer, with the addition of "but I will find out." On my exams a (fully) incorrect answer gets zero points while "I don't know but I will find out" gets one-half credit. You still fail if you don't know anything, but at least you are not in an idiot damned school system. Rewarding students for data dumps when they don't know an answer cannot be healthy. Or maybe I'm just biased because my approach makes exam grading significantly easier....

Bob, Unless guessing is part of finding out. (This clearly isn't the case in an exam, but often is in a classroom situation.)

Eliezer, I hope you are considering writing a book based on this excellent series of essays you have been writing.

Conchis, the problem is guessing passphrases instead of anticipation-controllers.

Robin, I am indeed considering it, it will depend on how much raw material I can generate.

A student who said it was done by magic would, of course, have been correct. Because it was done by magic.

The teacher moved the plate when the audience wasn't looking. That is one of the ways magicians perform their tricks.

If they had used words such as "supernatural," "miracle," or "paranormal," then they would not have been discussing physics.

But good magicians are the best practical physicists.

Eliezer, are you also considering giving free copies of the book to people who frequent this blog? :-)

Eliezer, Agreed. (That was my original point.)

The larger experiment seems to me to be the teacher's looking for someone with an answer to the ENTIRE 'experiment' which includes a 'false' set up. This isn't about 'physics,' it's about overall discernment, much the same way a truly observant participant will 'see through a magic trick,' no mean feat. So, for me, "I don't know" is the only honest and complete answer. It denotes an empty glass which (at least) can be filled and restricts that answwer to a particular observer and does not make 'unknowable" a universal state. Answers which are "data dumps" lull the mind into not questing further. You cannot 'wake up' until you know you have been 'asleep.' AND THEN, there is power imbalance. In a really optimal teaching environment, any 'student' (regardless of age, sex etc.) could forthrightly ask of any 'teacher,' "Is this a set up?" How rare is that?

regretting the above typos

I find it difficult to believe that none of the students would have guessed that the plate was turned around.

At one of the websites I frequent the first paragraph of this article was posted.

I guessed the teacher had set up the plate and turned it around.

As a student of the theatre I am somewhat versed in the arts of "Illusion". There was one show where we set off a smoke bomb and lowered the lights at the end of the first act. We then had intermission At the beginning of the second act we set of a smoke bomb and raised the lights. It's amazing how many people wrote about how we made the prop appear out of nowhere on the stage. They edited the intermission out of their remembrance of the story.

This story quickly sprang to my mind and I realized that if you can fool someone into forgetting an intermission you can fool someone that had no idea what was done before they came into the room in the first place.

Eliezer, I have to disagree with some of what you wrote. The question was phrased as to give what you thought would be an answer. In such a setting "I don't know" would not be something to say -- silence would be the result. Additionally, if someone said "heat conductance?" they're not saying they DO know, but it's clearly a guess... and possibly without the question mark in their tone, they really are throwing it out as a guess with little or no confidence, while not believing with any confidence that it's the reason. Additionally, the setting is a 'trick', as the environment is set where the authority figure to teach is doing something in which there is an answer as to why that would happen without switching the plate before they entered the room. But, I would agree, that any kid with confidence saying something like "heat conductance", is a poor thing to do.

I don't think answering with "heat conductance" would be the same as magic if you didn't know the equations. I would say it would be like answering as "magic" if you didn't know what heat conductance was (the principal behind it). "Magic" is basically saying "no natural cause"... in a sense saying it's an unknown reason that you, Miss Physics teacher can't understand either. :)

Phew. This is just an 'ask a stupid question, get a stupid answer' situation.

Questions 'why' and 'what is' are metaphysical or semantic and have nothing whatsoever to do with science. The only reason why those are prevalent in education is that education sucks. Science is not a search for answers to "why X happens", even though it is popularized as such.

My school physics wasn't like this at all (eastern Europe here). I would have a problem to solve - how many watts of heating are required to maintain uniform temperature of 20 degrees Celsius in a 10x5x2.2m room with concrete walls of 20cm thickness and outside temperature of -20 degrees Celsius (you can look up thermal conductivity of concrete). A very reasonable question. In the end, you're good in physics not when you have some warm inner feeling of understanding, not when you can 'explain' why something happens, but when you can PREDICT what will happen and/or make things happen. Nature couldn't care less if you know or not "why" stone axe is good for killing a mammoth (or something), it doesn't care if you call it 'inertia' or something else.

Interestingly enough, my teacher, Chris. Alexander (author of A Pattern Language), recounts his entrance test for a physics degree at Cambridge. The applicants were asked to experimentally determine the magnetic field of the earth. He performed the experiment, and came up with an answer he knew to be wrong. Wrong by too large a margin to put down to experimental error. A smart chap, he had time to repeat the key part of the experiment, and recalculate - got the same answer. He used the last part of his time to write down his hypothesis for having achieved such a result. And, alone among the students, he was right. A massive electro-magnet was being used on the floor below as part of another experiment.

I believe the advice offered to me as an 18yr old physics student encountering similar circumstances was simply to show my workings and the incorrect result, and to add that I knew this was not the 'right' answer.

I have a bad memory for isolated facts (like names or past events), and comparatively poor ability to guess intended meaning of things people are talking about in real time. When I was younger, I would just randomly guess possible answers to patch over the gaps in my mental picture (with little chance for actual success) in situations where it was expected of me to know the answer. Generation of random explanations that have nothing to do with actually explaining the observations might sometimes be motivated by a similar psychological pressure to give some answer.

Now I say "I don't know" or "I don't understand", to the bewilderment of people who would expect better mental agility of me, but don't know me well enough.

I not so sure that when the student suggests "because of heat conduction", they are attempting to provide a full explanation.

I model their internal thinking more along the lines of "Well, I don't know for sure what's going on here, this is an obscure effect I've not come across before, but it seems plausible to me that it will be in some way connected with conduction, so I'll suggest that as a first step, and hope someone else can fill in the mathematical details for me."

It is closer to the situation when a company owner says to her managers "Production has dropped by 50% in the last quarter, what's the cause and what can we do about this?" and a manger replies "Well, I don't know for sure, but I think it might have something to do with the recent marketing campaign where we changed the product name to 'Yucko'."

I heard this in the popular 'Oxbridge Interview Question' genre, a long time ago. It actually makes great sense there, as a 1960s don would have had a coal fire burning in winter, when the interviews are done, and be able to turn the plate round between interviews. And the interviewer would be expecting everyone to know all the relevant laws, and be looking for exactly the right level of bewildered confusion and hypothesis generation that you're hoping for.

The point is not to guess the right answer (that's essentially random inspiration and the ability to detect trickery is irrelevant for physics). The point is to provoke a detailed conversation about physics.

Some of these stories are clearly apocryphal, and some of them have the ring of truth. This one seems a bit dodgy since the previous interview candidate could easily spread the information about the trick (and although that's rather irrational, candidates do do this). Although if a candidate guessed straight away, the interviewer could just use another stock question.

Unless I misunderstand, this story is a parable. EY is communicating with a handwaving example that the effectiveness of a code doesn't depend on the alphabet used. In the code used to describe the plate phenomenon, “magic” and “heat conduction” are interchangeable symbols which formally carry zero information, since the coder doesn't use them to discriminate among cases.

I’m sincerely confused as to why comments center on the motivations of the students and the professor. Isn't that irrelevant? Or did EY mean for the discussion to go this way? Does it matter?

"Because of heat conduction" is the correct answer-heat from the radiator conducts to the plate-heat from the plate conducts to the air regardless of which side is being examined. The teacher asked "Why does this happen?" not "Why is the closest side to the radiator cold and the distant side hot?"-the question which is assumed to be implied by the actual one. The answer to THAT question would be "because of magic" since the professor was performing an illusion that was prepared ahead of time. The data points necessary to divine the nature of the illusion (Mr. Wizard) would be: temp of the radiator, average air temp, temp of the cold side, temp of the warm side...that would be sufficient to demonstrate that "because of heat conduction" one side was closer to the radiator while the other was exposed to the air-despite the appearance of the opposite circumstances. Fake explanation FTW

Many different things can be deduced from this story, as previous comments have illustrated. The step that I question is "carries no information" = "magic". I prefer Karl Popper's account, in which [to paraphrase "Conjectures & Refutations" Chapter 1] "carries no predictive information" = "metaphysical" but "metaphysical" does not mean "unscientific". Rather, science involves two activities, hypothesis creation and hypothesis testing. It is the hypothesis testing that has to be exclusively empirical (confined to falsifiable hypotheses). There are no rules for arriving at new hypotheses according to Popper, only heuristics, and metaphysical arguments can often be a source of new insights that lead to new falsifiable hypotheses. I believe Imre Lakatos developed this distinction with his idea of "Research programmes" which cannot be falsified but get abandoned when they cease to be fruitful of falsifiable hypotheses. The commenters who have stressed that some of the student's wrong answers could be valuable first steps towards understanding fit into Popper's scheme. The question (which we can't answer) is whether the "password" status or the "first step" status was uppermost in their minds. To conclude, the posting is valuable in drawing attention to the disutility of password-type answers, but misleading in not also recognizing the role of first-step-type answers.

If you say "heat conduction", what experience does that lead you to anticipate? Under normal circumstances, it leads you to anticipate that, if you put your hand on the side of the plate near the radiator, that side will feel warmer than the opposite side.

Would you consider "black energy" as a fake explanation for the expansion of the universe?

(Response to old post)

These are students, so they don't have perfect understanding of science. Even if they understand how to calculate what some theories predict, they don't know exactly when to apply those theories or what confounding effects might occur.

So unlike someone with perfect understanding, they don't know with 100% certainty that any specific theory applies. Asking what caused X to happen is really asking "what theory, among the ones you know, has the highest probability of having caused this result".

But even if the result is wrong and no theory actually would lead to that result, the students would grant some non-zero probability that each theory produced that result (since they know they imperfectly understand the theories). There would still be a highest probability. They would then say "conduction" and they would be correct--the probability, given their limited understanding, that conduction produced this result is non-zero and greater than the probability for, say, convection.

I have seen this example before. I actually do not blame the students at all for the following reasons (some taken from other comments)

1) They are thinking out loud, so seeing that some aspects points it could be heat conduction(after all that would be the typical reason for most temperature discrepancies withing an item) then they scream "heat conduction" as an invitation for closer look which is a valid (as pointed by other commentors) method of thinking

2) They are screaming the highest probable answer they can think of. Magic and heat conduction are not the same in that case. The students know they do not know the answer for sure and they basically going for the most probable cause that exist in their mind database and isnt that how a theory is initially theorized? after initial stating it get questioned and removed or confirmed

3) This is a physics class. It is assumed you do not know the answer so guessing is a valid way to learn because imagine in a different situation when it was NOT a trick question and the answer was actually heat conduction. The student who GUESSED heat conduction will feel the joy of being right and probably will remember that lesson better for the future since he will link it to a happy specific incident in the class. I think the student aim for that feeling and it is a good thing because I believe it helps them actually learn [need memory learning references]

4) They know (assume) the teacher knows the correct answer, and thus guessing wrong answers is not bad since no one will take their word for it and instead wait for the final correct answer by the teacher. There is no harm at all to guess and try to rationale through all of your theories. Stating the topic of those theories is a valid first step since that's how we usually solve any physics problem (e.g. to calculate the speed of falling ball, you need to recognize which equation you should investigate, should it be conservation of energy or the acceleration equations. Stating the title then investigating till proven right or wrong is a correct way to address this problem. Part of solving a problem is recognizing the telltales that direct you to the right equation, this case had a lot of telltales for heat conduction)

5) While this relates less, but i do not blame the students for not figuring out the right answer because its probability is pretty low. If they never got trick questions from this teacher, it seems a pretty unreasonable thing to assume from a physics teacher during class.

6) I would guess most of the students who would say "i dont know" FAST without exploring those wrong theories will be the lazy and uninterested students. it is equivalent to giving up and shutting down your rationale.

I am pretty confident if this happened to me i will be one of the students who keep trying theories and discussing them with others. I learned a LOT of physics concepts through discussing ideas with bunch of students who none knew the right answer. Many times we were able to reach the right answer after several wrong ones. I think in this situation this what the students were doing and I approve of it [sadly my approval means nothing :D].

I was just re-reading the sequences, and I have to say that as a teacher I really think you're misjudging what is happening here.

Much of learning, it seems, is building up a mental framework, starting from certain concepts and attaching new concepts to them so that they can easily be recalled later and so you can use the connections between concepts to develop your own thinking later..

From my point of view, it looks like the student (perhaps as long as a year ago) had successfully created a new concept node in their mind, "heat conduction". They had connected this node to the concepts of heat transfer and physics. And even though they likely hadn't activated this node at all in perhaps a year, they were able to take a specific example of something they saw in the real world, generalize it to something that might be related to the more general topic of heat transfer in physics, and create a hypothesis of heat conduction.

If you saw a machine learning algorithm that was able to do all that, you'd really be impressed! Something like Watson might be able to go from the concept of heat transfer to heat conduction, but it wouldn't be able to generalize from a specific example of heat transfer it saw in the real world.

Now, they might not yet have a lot of details attached to the "heat conduction" concept node in their head. But that's ok, that they can learn, that gives you something to build on as a teacher. If you teach it well and they can attach some details and images and maybe some math to the concept of "heat conduction" in the head, then hopefully next time they'll say "Maybe heat conduction? Hmmm, no, that doesn't work." which is even better. But there's more going on here then just "guessing a password"; this is part of what constructing a model of the world looks like while the process is only partly completed.

• We can be swayed by the context we are operating in, thinking inside-the-box
• Don’t use terms and explanations if you are not really sure about the concepts

I can't find the quoted joke in scijokes.txt, can anyone help?

When you are presented with a very unlikely outcome you have to accept it.

Had the teacher shown a dozen dice all showing the same number and asked how he did it, there would have been two answers:

2. You

Had the teacher presented a dozen of dice all showing the same number and asked how this could have happened they would have been wiser.
But the situation is similar. In pure theory this could happen naturally, in that case doubting it would be a case of gamblers fallacy or not knowing the Anthropic principle.

If you encounter the impossible you should check your assumptions, but to say that a human like entity has caused this outcome is dangerous.

Perhaps it's worth distinguishing between two types of "I don't know":

1. I don't know because I haven't put any thought into it. (This is the type of "I don't know" that teachers rightly discourage.)
2. I don't know because I have considered several hypotheses, and none of them explain my observations. (For example, my mental model of heat conduction predicts that the close side of the plate should be hotter, not the far side, so that explanation fails.)

Perhaps teachers should encourage students to replace "I don't know" with "my mental model predicts A, but I observe B", which communicates that the student is thinking correctly about the problem.

Note that the nearer side feeling colder than the farther side is be completely possible.

 The key is that they didn’t check the temperatures of each side with a thermometer, but with their hands. And your hands don’t feel temperature directly, they feel heat conduction. If you have a cake and a baking tin that are the same temperature, the metal will feel hotter because it is more conductive.

If I wanted to achieve the effect described here without flipping trickery, I might make the side near the radiator out of a very nonconductive plastic (painted to look like metal), and the side further away out of a very thermally conductive metal. It seems entirely plausible to me that once everything is in thermal equilibrium, the plastic would feel cooler than the metal, despite having a higher temperature. Of course, this would depend on the actual temperatures, conductivities, etc involved. But in principle it seems completely possible. 

Suddenly the physics students don’t look so foolish. In fact, in this scenario, both the heat conduction guy and the “strange metals in the plate” guy are on the right track! (even the convective guy could have a point, if that's the primary method of heating the far side). They are acknowledging their confusion, while trying to suggest avenues of exploration that might reveal an aspect of the problem they didn’t think of. In this scenario, the  Rationalist who dismisses these answers is the real fool, acting as the curiosity stopper, just because they didn't think of how hands feel heat. (of course, the ideal reasoner would think of both "different metal" and "flipped plate" as hypotheses). 

There are a few key aspects to consider here:
1 The instructor is an authoritative figure. Students assume the question posed by the instructor is one with merit and that he isn't playing tricks on them.
2 This is a physics class, not a philosophy class? If it was the second one, students may be inclined to think outside the box. But nobody expects a physics teacher to be playing tricks on the experiments.
3 Students will always try to give their best guess if they're pressed for an answer.  "I don't know" is rarely an acceptable answer by any teacher.