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Disputing Definitions

43 Post author: Eliezer_Yudkowsky 12 February 2008 12:15AM

Followup toHow An Algorithm Feels From Inside

I have watched more than one conversation—even conversations supposedly about cognitive science—go the route of disputing over definitions.  Taking the classic example to be "If a tree falls in a forest, and no one hears it, does it make a sound?", the dispute often follows a course like this:

If a tree falls in the forest, and no one hears it, does it make a sound?

Albert:  "Of course it does.  What kind of silly question is that?  Every time I've listened to a tree fall, it made a sound, so I'll guess that other trees falling also make sounds.  I don't believe the world changes around when I'm not looking."

Barry:  "Wait a minute.  If no one hears it, how can it be a sound?"

In this example, Barry is arguing with Albert because of a genuinely different intuition about what constitutes a sound.  But there's more than one way the Standard Dispute can start.  Barry could have a motive for rejecting Albert's conclusion.  Or Barry could be a skeptic who, upon hearing Albert's argument, reflexively scrutinized it for possible logical flaws; and then, on finding a counterargument, automatically accepted it without applying a second layer of search for a counter-counterargument; thereby arguing himself into the opposite position.  This doesn't require that Barry's prior intuition—the intuition Barry would have had, if we'd asked him before Albert spoke—have differed from Albert's.

Well, if Barry didn't have a differing intuition before, he sure has one now.

Albert:  "What do you mean, there's no sound?  The tree's roots snap, the trunk comes crashing down and hits the ground. This generates vibrations that travel through the ground and the air. That's where the energy of the fall goes, into heat and sound.  Are you saying that if people leave the forest, the tree violates conservation of energy?"

Barry:  "But no one hears anything.  If there are no humans in the forest, or, for the sake of argument, anything else with a complex nervous system capable of 'hearing', then no one hears a sound."

Albert and Barry recruit arguments that feel like support for their respective positions, describing in more detail the thoughts that caused their "sound"-detectors to fire or stay silent.  But so far the conversation has still focused on the forest, rather than definitions.  And note that they don't actually disagree on anything that happens in the forest.

Albert:  "This is the dumbest argument I've ever been in.  You're a niddlewicking fallumphing pickleplumber."

Barry:  "Yeah?  Well, you look like your face caught on fire and someone put it out with a shovel."

Insult has been proffered and accepted; now neither party can back down without losing face.  Technically, this isn't part of the argument, as rationalists account such things; but it's such an important part of the Standard Dispute that I'm including it anyway.

Albert:  "The tree produces acoustic vibrations.  By definition, that is a sound."

Barry:  "No one hears anything.  By definition, that is not a sound."

The argument starts shifting to focus on definitions.  Whenever you feel tempted to say the words "by definition" in an argument that is not literally about pure mathematics, remember that anything which is true "by definition" is true in all possible worlds, and so observing its truth can never constrain which world you live in.

Albert: "My computer's microphone can record a sound without anyone being around to hear it, store it as a file, and it's called a 'sound file'. And what's stored in the file is the pattern of vibrations in air, not the pattern of neural firings in anyone's brain.  'Sound' means a pattern of vibrations."

Albert deploys an argument that feels like support for the word "sound" having a particular meaning. This is a different kind of question from whether acoustic vibrations take place in a forest—but the shift usually passes unnoticed.

Barry:  "Oh, yeah?  Let's just see if the dictionary agrees with you."

There's a lot of things I could be curious about in the falling-tree scenario. I could go into the forest and look at trees, or learn how to derive the wave equation for changes of air pressure, or examine the anatomy of an ear, or study the neuroanatomy of the auditory cortex.  Instead of doing any of these things, I am to consult a dictionary, apparently.  Why?  Are the editors of the dictionary expert botanists, expert physicists, expert neuroscientists?  Looking in an encyclopedia might make sense, but why a dictionary?

Albert:  "Hah!  Definition 2c in Merriam-Webster:  'Sound:  Mechanical radiant energy that is transmitted by longitudinal pressure waves in a material medium (as air).'"

Barry:  "Hah!  Definition 2b in Merriam-Webster: 'Sound:  The sensation perceived by the sense of hearing.'"

Albert and Barry, chorus:  "Consarned dictionary!  This doesn't help at all!"

Dictionary editors are historians of usage, not legislators of language. Dictionary editors find words in current usage, then write down the words next to (a small part of) what people seem to mean by them.  If there's more than one usage, the editors write down more than one definition.

Albert:  "Look, suppose that I left a microphone in the forest and recorded the pattern of the acoustic vibrations of the tree falling.  If I played that back to someone, they'd call it a 'sound'!  That's the common usage!  Don't go around making up your own wacky definitions!"

Barry:  "One, I can define a word any way I like so long as I use it consistently.  Two, the meaning I gave was in the dictionary.  Three, who gave you the right to decide what is or isn't common usage?"

There's quite a lot of rationality errors in the Standard Dispute.  Some of them I've already covered, and some of them I've yet to cover; likewise the remedies.

But for now, I would just like to point out—in a mournful sort of way—that Albert and Barry seem to agree on virtually every question of what is actually going on inside the forest, and yet it doesn't seem to generate any feeling of agreement.

Arguing about definitions is a garden path; people wouldn't go down the path if they saw at the outset where it led.  If you asked Albert (Barry) why he's still arguing, he'd probably say something like: "Barry (Albert) is trying to sneak in his own definition of 'sound', the scurvey scoundrel, to support his ridiculous point; and I'm here to defend the standard definition."

But suppose I went back in time to before the start of the argument:

(Eliezer appears from nowhere in a peculiar conveyance that looks just like the time machine from the original 'The Time Machine' movie.)

Barry:  "Gosh!  A time traveler!"

Eliezer:  "I am a traveler from the future!  Hear my words!  I have traveled far into the past—around fifteen minutes—"

Albert:  "Fifteen minutes?"

Eliezer:  "—to bring you this message!"

(There is a pause of mixed confusion and expectancy.)

Eliezer:  "Do you think that 'sound' should be defined to require both acoustic vibrations (pressure waves in air) and also auditory experiences (someone to listen to the sound), or should 'sound' be defined as meaning only acoustic vibrations, or only auditory experience?"

Barry:  "You went back in time to ask us that?"

Eliezer:  "My purposes are my own!  Answer!"

Albert:  "Well... I don't see why it would matter.  You can pick any definition so long as you use it consistently."

Barry:  "Flip a coin.  Er, flip a coin twice."

Eliezer:  "Personally I'd say that if the issue arises, both sides should switch to describing the event in unambiguous lower-level constituents, like acoustic vibrations or auditory experiences.  Or each side could designate a new word, like 'alberzle' and 'bargulum', to use for what they respectively used to call 'sound'; and then both sides could use the new words consistently.  That way neither side has to back down or lose face, but they can still communicate.  And of course you should try to keep track, at all times, of some testable proposition that the argument is actually about.  Does that sound right to you?"

Albert:  "I guess..."

Barry:  "Why are we talking about this?"

Eliezer:  "To preserve your friendship against a contingency you will, now, never know.  For the future has already changed!"

(Eliezer and the machine vanish in a puff of smoke.)

Barry:  "Where were we again?"

Albert:  "Oh, yeah:  If a tree falls in the forest, and no one hears it, does it make a sound?"

Barry:  "It makes an alberzle but not a bargulum.  What's the next question?"

This remedy doesn't destroy every dispute over categorizations.  But it destroys a substantial fraction.

 

Part of the sequence A Human's Guide to Words

Next post: "Feel the Meaning"

Previous post: "How An Algorithm Feels From Inside"

Comments (30)

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Comment author: brent 12 February 2008 01:23:13AM 2 points [-]

ech...

"Abortion is murder because it's evil to kill a poor defenseless baby."

I am so sick of arguing with people who's definition of the issue constitutes 99% of their argument, and who aren't willing to acknowledge that their definition needs consensus before their point is even meaningful let alone valid.

Like you say - most of the time an argument is completely settled once/if everyone agrees one the terms being used.

Comment author: DanielLC 08 July 2011 05:08:21AM 4 points [-]

I would say that if it is evil to kill a poor defenseless unborn baby, then murder should probably be defined to include abortion. The problem is when people say "It's evil to kill a poor defenseless baby because abortion is murder."

Comment author: po8crg 24 March 2012 01:56:31PM 11 points [-]

The problem is that it begs the question - using "unborn baby" defines it into the same ethical category as a born baby, different only in location. When you dig down enough, usually that's the point at dispute - is the thing growing in a womb entitled to rights in the manner of a (born) baby, or is it not so entitled.

There are some property-rights thinkers who do hold that it is the location that matters, i.e. the baby is trespassing on the mother's womb, and she's entitled to use deadly force to remove it, but that's not the usual argument.

Comment author: TheOtherDave 24 March 2012 02:25:07PM 2 points [-]

Upvoted entirely for using "begs the question" correctly.

But, to respond to the comment -- there is also the position that the extent to which we should act to prevent my life from ending depends significantly on the costs of sustaining my life and who bears those costs, and since the cost equation typically changes significantly for an 35-week-old fertilized egg and a 45-week-old fertilized egg, it's reasonable to reach different conclusions about what acts are justified in those two cases.

And one can adopt that position whether the 35-week-old fertilized egg is called an "unborn baby," a "fetus", a "uterine growth", a "upcoming blessed event", a "little leech," or whatever. (All of which are terms I've heard pregnant women use to describe their fertilized egg at various stages of gestation.

The same principle suggests that we don't treat a 45-week-old fertilized egg the same as a thousand-week-old fertilized egg.

But I agree with your implicit point that many thinkers on the subject, as well as many speakers on the subject who may or may not be doing much thinking at the time they speak, respond primarily to the connotations of those terms.

Comment author: Doug_S. 12 February 2008 03:35:56AM 14 points [-]

Suppose I order a blegg from a mail-order catalog. As it turns out, the object I received is blue and is furry, but it is cube-shaped, does not glow in the dark, and contains neither vanadium nor palladium. I am disappointed and attempt to return the object, claiming that it is not, in fact, a blegg. The seller refuses to give me a refund or exchange the object for another. Annoyed, I decide to take the seller to court.

Would I win the lawsuit?

(This is why arguments over definitions have real-world consequences.)

Comment author: halcyon 07 April 2012 06:34:55AM 7 points [-]

Sorry, just... no. I realize it's been four years, but I had to create an account just to register my disapproval. The question remains, what did you want from the blegg? Vanadium or Palladium? Its glow-in-the-dark property? A gestalt effect arising from the combination of certain salient features? What does any of this have to do with consensus-based definitions?

Comment author: ete 26 April 2014 10:26:28PM 2 points [-]

I find it quite interesting that despite the two above posts having very strongly contradictory points they both a large number of upvotes are are both at 100% positive (15 and 8 at the time of writing). I wonder whether the community's opinion has shifted over the years, or whether lw voters just think both points are well put and are very reluctant to downvote things based on disagreeing with a point.

</offtopicnecrometapost>

Comment author: Caledonian2 12 February 2008 03:50:02AM 3 points [-]

Using different words to describe the same thing can produce a dispute where there is none, yes. But people also tend to use the same word to refer to totally different things, sometimes as a means of artificially avoiding conflict. Equivocation can be a powerful teaching tool and rhetorical device, but more often it serves as a way to lie plausibly, both to others and to oneself.

Meaningful communication is possible only when people are discussing the same ideas, and ensuring that everyone involved maps the same concepts onto the same words is necessary to bring that about.

Without concern for the proper use of words, language becomes useless.

Comment author: Eliezer_Yudkowsky 12 February 2008 06:30:36AM 14 points [-]

Would I win the lawsuit? This is why arguments over definitions have real-world consequences.

Technically, that's not so much an argument over a definition, as an argument over cognitive history: The seller's expectation of your expectation of what you would get in the mail; and the application of the law to those expectations.

I did mention that the remedy is not universal. If people have already taken actions, based on their previous communications, then the consequences are already set in motion - you can't go back in time and use the remedy.

Abortion is murder because it's evil to kill a poor defenseless baby.

Another time you can't just generate new words is when a category boundary like "person" or "human" or "baby" makes a direct appearance in your utility function.

Comment author: Ron_Hardin 12 February 2008 10:46:51AM 1 point [-]

People can agree about all the facts but argue about what the word means, which question is an empirical one. People don't know what their criteria are for something being a sound, and can only offer aspects that seem to count for it or against it. You have to try the argument and see if you can see it that way.

Perhaps in the end you can bring out what a sound is.

See Cavell on chairs, op cit. and derivatively Wittgenstein.

The people arguing are not making a mistake; the cognitive scientist is.

Comment author: Ben_Jones 12 February 2008 02:10:02PM 5 points [-]

Without concern for the proper use of words, language becomes useless.

A valid point, as long as you're careful that language work for you and not vice versa. The moment you find the expression of your concept being stifled by grammar or vocabulary or tradition, find another way. Invent a new word; define it using comparison, differentiation, pictures, hand signals, noises. Language should bend to incorporate reality; otherwise the tail is wagging the dog. Language has enormous power to make our world, hence the sort of typical argument Eliezer discusses. But we should never lose sight of the fact that it is our tool, and any rules should be enabling rather than restrictive - clarity of communication is the goal.

Comment author: thodirycgoyust 15 August 2011 09:08:23AM 2 points [-]

This is why I advocate the adoption of logical language(s). Those in the tradition of Loglan, for example, share vocabularies and grammars designed such that context can be made irrelevant given appropriate sentence construction (some other ambiguity reducing features as well), and tools to easily make temporary (ie: until end of conversation) extensions to their vocabularies where the base is insufficient while generally behaving like natural language.

Comment author: paper-machine 15 August 2011 09:23:41AM 0 points [-]

And yet as far as I'm aware, it's impossible to infer the place structure or semantics of a predicate. This is a massive problem in Lojban (who knows or cares if it's in Loglan -- the language is kept as a trade secret, after all).

E.g., I could print pamphlets defining 'klama' as standard 'se klama' and it would take a while for anyone to notice the difference.

Comment author: lessdazed 15 August 2011 10:16:48AM *  1 point [-]

Let's discuss partial solutions.

Suppose you and random other English speakers were abducted by aliens and accelerating out of the solar system on their ship. You strongly suspect you will never be able to go back, and get to work on building a new society.

You are the smartest person in the group and convince everyone that language is important. They agree to reform the language, but aren't capable of constructing or learning a new one, and aren't interested in teaching their children one. What simple reforms might be a good idea?

I can suggest some:

It will no longer be correct to say that something is (a color or similar property). One must say it "seems" a color, as well as to whom. Not "Snow is white", rather, "Snow seems white to me".

"Rationalize" will be replaced by a word with a different root.

Comment author: Caledonian2 13 February 2008 12:04:25AM 0 points [-]

The moment you find the expression of your concept being stifled by grammar or vocabulary or tradition, find another way.

No. First, you must check to confirm that your concept is potentially expressible. Some 'concepts' are self-contradictory and cannot be further talked about for that reason. There is nothing more than can be said about "the encounter of an immovable object with an irresistible force" beyond that it is invalid. Trying to find another way either leads to the eventual recognition that nothing else can be expressed, or (more likely) ends in our using language as a screen to prevent the incompatibility from entering our awareness.

Comment author: o 13 February 2008 12:30:49AM 0 points [-]

Eliezer,

I would just like to tell you I very much enjoyed this post. I love debate but find they often go awry in ways such as above. More like this. Or, can you post links to others like this from before?

Comment author: taryneast 10 December 2010 10:08:02AM *  1 point [-]

Just to say - I recognise this comment was left several years ago... and probably before the sequence page was written, but for those who follow after, you can follow along here:

http://lesswrong.com/lw/od/37_ways_that_words_can_be_wrong/

Comment author: Ben_Jones 13 February 2008 09:20:18AM 1 point [-]

...the encounter of an immovable object with an irresistible force...

Reread me Caledonian - this is a problem with logic; not a problem with language. You had no problem expressing it verbally, so it's not the kind of thing I'm talking about.

Comment author: tommyjohn 18 November 2011 09:58:30PM 0 points [-]

Is this a problem with logic or a linguistic expression of a paradox?

Comment author: gutzperson 13 February 2008 11:10:18AM 1 point [-]

Language (systems) can never be precise, only as precise as possible. At its best it is about the least misunderstanding; misunderstanding being inherent. Approximation comes into my mind. It is about agreements (also the breaking of these) and closed circuit situations. At its best it is about more or less successful feedback loops.

Comment author: Caledonian2 13 February 2008 02:22:57PM 0 points [-]

You had no problem expressing it verbally

1) There are still people who insist that if we can talk about it, it must be real.

2) Logic is just language used very, very precisely. Reinventing language in an attempt to make one's point may be useful, even necessary, but it tends to be a means to disguise contradictions in logic by hiding them within unfamiliar terms and usages.

But we should never lose sight of the fact that it is our tool, and any rules should be enabling rather than restrictive

Language is enabling only because it is restrictive. Remove the restrictions and you lose the meaning. Logic is a tool that we cannot command, only obey.

Comment author: Ben_Jones 13 February 2008 03:34:36PM 0 points [-]

That's easy for you to say.

Comment author: Richard_Hollerith2 13 February 2008 05:34:39PM 2 points [-]

Eliezer said that another time you can't just generate new words is when a category boundary like "person" or "human" or "baby" makes a direct appearance in your utility function.

Which gently suggests that when defining a utility function that might remain in force for billions of years, one should prefer functions that do not have category boundaries.

I would be happy to exhibit functions of that sort that have the property that even after an explosion of engineered intelligence, the humans probably retain enough expected utility to keep them flourishing and protected from exploitation although they probably do not retain enough expected utility to cause the majority of the future light cone's space, time, matter, free energy and other resources to be devoted to them.

Comment author: Fyrius 25 March 2010 08:04:45AM 2 points [-]

"Pickleplumber" is now my favourite swearword.

Comment author: drewski 16 May 2010 03:36:03AM *  1 point [-]

If only everybody would search for more clarity in communication.

I think in the words I speak in to create logic in my mind. So not only does using a words with fuzzy definitions, exaggerating or twisting sentences affect my ability to communicate clearly, it affects my ability to think clearly.

Barry and Albert could have avoided argument if they saw being proven wrong as something that should be celebrated because their mind has been raised to a new level of understanding. Rather than a defeat. Then their focus would have been on understanding each other rather than defending their position.

Comment author: DanielLC 08 July 2011 05:05:42AM 1 point [-]

So is this what that dispute was? I always thought it was more of a solipsism thing, but that doesn't make much sense because then the question should be "Does the tree actually fall, or is it up when you first see it, down later on, and nonexistent in between?"

Comment author: olalonde 25 April 2012 04:50:58PM *  3 points [-]

One way to get around the argument on semantics would be to replace "sound" by its definition.

...

Albert: "Hah! Definition 2c in Merriam-Webster: 'Sound: Mechanical radiant energy that is transmitted by longitudinal pressure waves in a material medium (as air).'"

Barry: "Hah! Definition 2b in Merriam-Webster: 'Sound: The sensation perceived by the sense of hearing.'"

Albert: "Since we cannot agree on the definition of sound and a third party might be confused if he listened to us, can you reformulate your question, replacing the word sound by its definition."

Barry: "OK. If a tree falls in the forest, and no one hears it, does it cause anyone to have the sensation perceived by the sense of hearing?"

Albert: "No."

Comment author: ToddStark 17 December 2012 05:51:29AM 0 points [-]

"... replace "sound" by its definition."

Yes, that's exactly what happens in a reasonable dialog, at the point where people realze they are thinking of the same thing in different ways. The trick is recognizing what that difference is so you can expand on it and compare. It happens fairly quickly and easily in most cases when both people are mostly focused on inquiry. If they are arguing their own position, they are unlikely to be looking for the difference, they are probably looking for ways to deconstruct the other person's terms and find fallacies in their logic or problems with their evidence. They will resort to arguing for their own definitions.

When you end up in a game of duelling definitions, one valuable strategy is to ask the purpose of the definition. It serves a rhetorical purpose to use one definition vs. another in an explanation or question. If emphasizes different things. This is an important pragmatist principle coming from the slant that words are tools for thinking.

Ex:

Q: Why bring the perceiver into the picture when talking about sound? What purpose does that serve?

A: The reason I define sound as something perceived is to distinguish the dark, silent physical world of wavelengths and vibrations and strings from the one constructed in human experience to operate on the world. I care about the human experience, not what is going on with atoms.

This exposes a great deal of the relevant conceptual background and current focus of each person so you know what they are arguing about and might be able to either collaborate more effectively, learn something from each other, or else identify that you aren't talking about the same thing at all. Rather than just fighting over which definition is better.

Comment author: chaosmosis 03 May 2012 04:11:43AM 2 points [-]

Well-done definition debates are still possible. But they're about the comparative usefulness of conceptualizing X in a certain way Y as opposed to a different way Z, and vice versa. Well done definitional debates can actually be really interesting though, although they don't crop up too much.

Comment author: [deleted] 13 June 2014 10:50:28AM -2 points [-]

Here's an alternative guide to words:

'' Component display theory M. D. Merrill’s Component Display Theory (CDT) is a cognitive matrix that focuses on the interaction between two dimensions: the level of performance expected from the learner and the types of content of the material to be learned. Merrill classifies a learner’s level of performance as: find, use, remember, and material content as: facts, concepts, procedures, and principles. The theory also calls upon four primary presentation forms and several other secondary presentation forms. The primary presentation forms include: rules, examples, recall, and practice. Secondary presentation forms include: prerequisites, objectives, helps, mnemonics, and feedback. A complete lesson includes a combination of primary and secondary presentation forms, but the most effective combination varies from learner to learner and also from concept to concept. Another significant aspect of the CDT model is that it allows for the learner to control the instructional strategies used and adapt them to meet his or her own learning style and preference. A major goal of this model was to reduce three common errors in concept formation: over-generalization, under-generalization and misconception.''