While we're staking out the new language, I want a word for red flowers, because I like red flowers, and that is much more important to me than their genotype or taxonomy. Also, I want a special word for slightly-out-of-focus photos, which is a very important category for reasons I'm not at liberty to disclose. The joints of reality are articulated in a rather large number of dimensions. Carving it correspondingly is going to need one heck of a .... dictionary.

Just a small one, because I can't hold it: You can't judge the usefulness of a definition without specifying what you want it to be useful for. And now I'm off to bed... =)

Just because there's a word "art" doesn't mean that it has a meaning, floating out there in the void, which you can discover by finding the right definition.

True, but it strongly suggests that people who use the term believe there is a referent for it. Sometimes there is none (eg "phlogiston" or "unicorn"). Sometimes the referent is so muddled or misunderstood that the term is has little use except to name the mistake (eg "free will", which seems to function as a means of grouping quite distinct concepts of subjective freedom together as if they were the same thing, or "qualia" whose referent is a subjective illusion)

But almost always it's worth asking what they think they mean by it.

@tcpkac, we sometimes call slightly-out-of-focus photos "blurries". Hope that helps with your important secret project. }:)

"I think it has to do with admiration of craftsmanship: work going in and wonder coming out. What the included items have in common is the similar aesthetic emotions that they inspire, and the deliberate human effort that went into them with the intent of producing such an emotion."

Yeah, that's a lot like what I said. ;) It's not a perfect Aristotellian or mathematical definition, but it's about as good as any other phrase I can think of to point at the similarity cluster commonly called "art". Also, "art" is a word used to sneak in the connotation "worthy of respect and appreciation", as illustrated by a question like "Can [X] be art?" where X could be a video game, mathematical proof, programming language, newspaper editorial, photograph, comic book, or anything else that some people admire and some don't.

/me shrugs

More fun with words:

Programming is the art of figuring out what you want so precisely that even a machine can do it.

Diplomacy is the art of saying "Nice Doggie" while you find a rock.

Politics is the art of looking for trouble, finding it everywhere, diagnosing it incorrectly, and applying the wrong remedies.

Leadership is the art of getting someone else to do something you want done because he wants to do it.

(Bonus points for finding a source for each of these quotes.)

Wrt defining art, I offer my definition:

"An artifact whose purpose is to be perceived and thereby produce in its perceiver a positive experience of no direct practical value to the perceiver."

"Artifact" here is meant in the sense of being appropriate for Daniel Dennett's design stance. It is not neccessarily tangible or durable.

This is what's called a Genus-differentia definition, or type-and-distinction definition. "Artifact" is the type, the rest is the distinction.

This lets me build on existing understandings about artifacts. They have a purpose, but they remain artifacts even when they are not accomplishing that purpose. They are constructed by human beings, but this is a pragmatic fact about human ability and not a part of their definition.

I avoided terms that make no definitional progress such as "beauty" and "aesthetic". Using them would just be passing the buck.

This definition seems to include birdsong. Make of that what you will. One could reasonably say that birdsong is a fitness signal of direct practical value to the intended perceiver, though.

Under this definition, throw-the-paint art is not so much excluded as it is a marginal, failed, or not serious example, much the way that a hammer (which is another type of artifact) constructed of two twigs scotch-taped together at right angles is a failure as a hammer

(This would mark you as a gullible philistine, but you could argue it.)

I'd much rather be marked as a gullible philistine than be blind to the wonder of Joyce, Messiaen, and Rothko.

"You come up with a list of things that feel similar, and take a guess at why this is so."

Yes, I agree with this entirely. When we observe a scene, what we "automatically receive" on the perceptual level is: sight, sound, smell, touch, taste and similarity (in the form of a feeling). We are just automagically aware that two objects are similar, without going through any (conscious) logical steps to get that knowledge.

Whenever I think about AI design I model similarity as one of the senses.

I disagree with you (kind of). The fact that the word art exists does, in fact, imply that it has a meaning...for each individual who uses it.

There are no absolute classifiers. Even if there were, we could not know them. Our knowledge is necessarily defined in terms of our own experience and the computations we have performed on this experience.

It is useful to think of the "meaning" of a term as the way in which that term relates to more primitive terms. This is not necessarily a list (e.g. Post-modernism cannot be defined in terms of a list). This might be a deduction - a history of deduction - whatever. For instance, what is a good definition for "Post-Modernism?" Perhaps we must appeal to a large body of knowledge - the point is that the result, the "meaning," must be at minimum useful to perform computations (computations above and beyond classification, btw - a reason that meaning can include non-necessary information).

So can we justifiably ask the question "what is the meaning of art?"

Sure, but my claim is that this is a massively sugared/somewhat poorly expressed question rather than an assertion of the absolute existence of the term "art" and the absolute existence of its definition. The questions we might really be asking (perhaps in parallel) are:

What is the use of a definition of art? What is a useful definition for art? Can a single definition exist (which satisfied all of our classifications)? Are our classifications wrong or strange? What is my personal definition of art? What is the context in which we are trying to define art?

The attempt to answer the question "what is the definition of X?" is often really the attempt to examine a deeper, more difficult to explain question. For instance, in the context of the example of "if no one hears a tree fall, does it make a sound" the question "what is the definition of sound?" can really be multiple questions (one or more of the questions above).

My claim is that people are not good enough at de-sugaring their own questions to actually attack them/think about them flexibly/precisely. Let me propose a simple mechanism which I think produces this phenomenon:

You have a conflict of definition (e.g. you and a friend disagree on whether Modern Art is in fact Art). On a computational level you might realize what the problem is. Perhaps you do not have a well-established context (since the definition of the term depends on context). Perhaps you have had significantly different experiences of things which "are modern art" in the sense of being culturally accepted as such. But in either case you are probably too inarticulate to explain exactly what the conflict is. Thus, you use the only tool available to you. You flail around and try to concoct a lingusitic expression of your conflict. You ask "well, what's your definition of ART then!?!"

I think that we perform this sort of operation a lot:

Well articulated intuition -> linguistic expression (loses resolution) -> poorly articulated intuition.

(another simple example of this phenomenon is an exasperated inarticulate man yelling "god, i hate women" - probably he does hate all women or claim anything general about women . He just doesn't have sufficient articulation to say "i am frustrated by my lack of success with women and do not understand them and therefore my frustration grows with each failed attempt at mating one - in addition, i experience a feeling of lack of self-worth which adds to my frustration and further confuses me." After he says "I hate women" he might actually believe he hates women since he re-translates his linguistic statement into feelings/belief.)

What are your thoughts on this phenomenon? I'd really like to know.

Do you think that a significant portion of the population harbors implicit or explicit delusions that words exist as absolutes and have definitions which also exist as absolutes? Or do you think something more complicated is going on? What, precisely, is the nature of the bias?

Tim, what would mark you as a gullible philistine is not just claiming that Modern Art is art, but also claiming that the Python programming language is not art - the combination of the two.

Well, I'm glad to hear that I'm off the hook, since I have no problem regarding Python as art (although I'm a Ruby man myself). That said: do you really mean that, given the set { Python, The Rite Of Spring, Beethoven's Ninth }, the natural joint is { Python, Rite } | { Ninth }, and that this is so obvious that people who disagree deserve to be called rude names? If so, why? If not, what do you mean?

Also, it's been a while since I read the Tschai books, but my recollection is that The Dying Earth is way better.

Speaking of Vance, he included the following musings on art and artifacts in one of his novels:

"Silence was absolute, save for the purl of water under the hull. At night a pair of large moons cast a serene light through the foliage in a manner which Maihac found almost dreamlike in its effect. He said as much to Bariano, who responded with a condescending shrug. "I am surprised to find you so enthusiastic. It is, after all, a mere trick of nature." [...] "It is simply that your aesthetic judgments are amorphous. It is naive to detect beauty where none has been specifically intended. The subject is large. Often you will notice an agreeable aspect of nature, effected by random or mathematical processes. It may be serene and congenial, but it is the work of chance and lacks the human afflatus. There is no pulse of positive creativity to infuse it with true beauty.""

Eliezer, This is a bit naughty. TABOOing art on one thread and elaborating on art on this one. In my experience, 'art' is used like a sponge. Everybody can do with it what they want. Squeeze it, make it woolly, throw it into your face, or talk about the art of science (a paradox!) for example, etc. etc. I should know a bit about this. I am an artist and have taught art at universities for twenty years. There are as many definitions as there are water drops in Lake Victoria. Quote: So I reply: "I think it has to do with admiration of craftsmanship: work going in and wonder coming out. What the included items have in common is the similar aesthetic emotions that they inspire, and the deliberate human effort that went into them with the intent of producing such an emotion." Modern art does not have that much to do with craftsmanship anymore, more with concepts, context and 'everybody could be an artist' if ...... At the end, your home movies, put into the right context (a museum) with a good description why it is art, describing a concept of making home movies for audiences in museums, with shaky camera movements, out of focus (no craftsmanship needed) could be a piece of art. Recontextualisation is a keyword.

P.S. Tim - that wasn't aimed as a correction of your argument, just an observation.

"You can't judge the usefulness of a definition without specifying what you want it to be useful for."

This was going to be my point:

"Once upon a time it was thought that the word "fish" included dolphins. Now you could play the oh-so-clever arguer, and say, "The list: {Salmon, guppies, sharks, dolphins, trout} is just a list - you can't say that a list is wrong. I can prove in set theory that this list exists. So my definition of fish, which is simply this extensional list, cannot possibly be 'wrong' as you claim."

Or you could stop playing nitwit games and admit that dolphins don't belong on the fish list."

I totally see your point, but I think it's worth exploring why the "nitwit" set is plausible, and why you feel the best defense against a cheeky definition is is an ad hom.

In this instance, I think the answer is that you're drawing the boundary line for one reason, and they are being twitty and drawing the boundary line arbitrarily just because they think the rules of logic allow them to do so with impunity (ad hom away).

However, I can think of a legitimate reason to draw the boundary in the nitwit way: what if I want a label whose members are all creatures that live in water and use fins to propel themselves? That's a legitimate category, but it certainly isn't a boundary appropriate for the word "fish," which has taxonomical implications, as well as physiological implications more complex than "has fins."

It may be worth pointing out to the nitwit that he's drawn a logically valid boundary, but it's not the territory you're talking about. Allow him his Fishoids, but steer the conversation back to creatures who have gills and lay eggs. Ideally you can get away with convincing the nitwit to re label HIS category so you can use the real fish label to avoid confusion, but in the interests of continuing a productive conversation, you might consider relabeling the boundary you mean to something neutral ("Gill Creatures"), that your opponent won't be so comfortable changing arbitrarily.

Haven't read any of the comments, but this seems pretty relevant to what Kripke gets into in the last section of Naming and Necessity.

However, I'm too tired to read it again -- could someone comment on this?

the quality, production, expression, or realm, according to aesthetic principles, of what is beautiful, appealing, or of more than ordinary significance.

This definition has the advantage of eschewing the pointless essentialism of trying to decide whether any specific object "is" art. If you drive a nail with an unshaped rock, it's a tool, at least for the moment; if you get an aesthetic experience from something, it's art, at least for the moment.

There is no 'natural joint'.

In which case, "natural joint" is as good a category as any, no?

But sure, it's just shorthand, for me anyway.

This has ruined my dreams of finding the true meaning of Christmas.

Psychoh, do not despair. Remember : "The real challenge can be played as a single-player game, without speaking aloud.". We are looking for the natural joints of reality, and that is a purely subjective assessment. Every single pair of phenomena in the Universe can be the subject of a natural join if the difference in one of their attributes happens to be a salient division for you. So draw the line around Christmas any way you want, just like you can draw the line around 'food things living in the sea' any way which is relevant to your way of fishing. Just don't speak it aloud.

I think this is an important point but I don't think you take it far enough. Language is for communication. One use of language is communicating science. It's not a scientific challenge to realize you need a single word to describe breathing and fire. The words merely communicate the science; science has nothing to do with words or with "carving the world up" into words. Indeed natural language often fails to communicate science; scientists have to rely on formalizations.

The next step is to apply this to all of human psychology and realize that no aspect of human psychology relates to the world in any way; it's convention all the way down.

"Once upon a time it was thought that the phrase "aquatic animal" included dolphins. Now you could play the oh-so-clever arguer, and say, "The list: {Salmon, guppies, sharks, dolphins, trout} is just a list - you can't say that a list is wrong. I can prove in set theory that this list exists. So my definition of aquatic, which is simply this extensional list, cannot possibly be 'wrong' as you claim." Or you could stop playing nitwit games and admit that dolphins don't belong on the aquatic animal list."

Quoted and altered for emphasis.

If we reject the idea that the conventional meaning of words should restrict us, why is it a 'nitwit game' to call dolphins, fish? 'Fish' can mean whatever we like it to - just because the word is used in science to refer to things that aren't mammals doesn't mean we have to use it that way.

This seems to be a little consistency problem.

Caledonian, octopi have never been considered fish.

They are aquatic animals. But that is irrelevant - the argument is being made with dolphins. And that is irrelevant, because the point concerns why failing to use a word in the conventionally-accepted manner is suddenly a "nitwit game", not which word is used to make this curious argument.

Seeking the "real meanings" of words is neither useless nor futile. The point is to recognize that definitions are not a matter of objective and universal truth but of societal labeling convention. What we're seeking is a deeper, explicit understanding of that convention.

Go back a few thousand years and try telling a fisherman that dolphins aren't fish. He'd look at you like you were a fool - which you of course would be.

The word, "fish", is not the real issue. What actually matters is that including dolphins in that category leads to making incorrect inferential predictions ("Salmon, guppies, sharks, and trout all lay eggs, so dolphins probably do too.") as well as weakening the ability to make correct ones ("Do trout have gills? Well, salmon do, but dolphins don't, so who knows.")

What kinds of properties is your "aquatic animals" category better at predicting? (And "living in water" doesn't count, because that's what you have to already know to see if something's in the category.)

Octopi were never considered fish but were always considered aquatic animals. They simply aren't fish and neither are dolphins. If I argue with a fisherman of a few thousand years ago I will have the more correct understanding because things have been learned about these animals in between the time he lived and I do.

Goplat - excellent post.

What actually matters is that including dolphins in that category leads to making incorrect inferential predictions [...] as well as weakening the ability to make correct ones.

First off, making any inferential predictions based solely on the fact that two things are in the same category is unwise. Inferences are strong when they are founded in a wide and deep knowledge base. They are always weak when founded on a single point, regardless of what that point is. If we know nothing about the sorts of things that are included in 'aquatic animals' or the criteria that defines the category, having only two examples doesn't permit us to conclude much of anything about how similar those things are.

Secondly, if we try to make category-based inferences anyway, any categorical distinction lends itself to the errors you've mentioned. Even two dolphins have many things that are different between them. That is not a reason to refuse to have the category 'dolphin' or to place things in it.

What kinds of properties is your "aquatic animals" category better at predicting?

Categories and labels are not supposed to be used to predict anything. That is not their purpose or function, and not surprisingly, they are not well-suited for the task. They are used to indicate that a specific set of similarities hold: this set can include many different properties, or only a single one. They say absolutely nothing about additional properties. They're descriptions, and descriptions only.

When words permit us to make additional predictions about properties that we care about, we find those categorical distinctions more useful than others. But useful is not the same as correct, and any correct distinction has an inherent usefulness.

"You cannot hide behind a comforting shield of correct-by-definition. Both extensional definitions and intensional definitions can be wrong, can fail to carve reality at the joints. "Categorizing is a guessing endeavor, in which you can make mistakes; so it's wise to be able to admit, from a theoretical standpoint, that your definition-guesses can be "mistaken"."

I agree heartily with most of this post, but it seems to go off the rails a bit at the end in the section I quote above. Eliezer says intensional definitions (that is, categorizations based on the arbitrary highlighting of certain dimensions as salient) can be "wrong" (i.e. untrue) because they fail to carve reality at the joints. But reality, in its full buzzing and blooming confusion, contains an infinite numbers of 'joints' along which it could be carved. It is not at all clear how we could say that focusing one some of those joints is "true" while focusing on other joints is "false," since all such choices are based on similarly arbitrary conventions.

Now, it is certainly true that certain modes of categorization (i.e. the selection of certain joints) have allowed us to make empirical generalizations that would not otherwise have been possible, whereas other modes of categorization have not yielded any substantial predictive power. But why does that mean that one categorization is "wrong" or "untrue"? Better would seem to be to say that the categorization is "unproductive" in a particular empirical domain.

Let me make my claim more clear (and thus probably easier to attack): categories do not have truth values. They can be neither true nor false. I would challenge Eliezer to give an example of a categorization which is false in and of itself (rather than simply a categorization which someone then used improperly to make a silly empirical inference).

PH, my reply is contained in Mutual Information, and Density in Thingspace.

Typo: eluctromugnetism should be electromugnetism

The definition of art begins to matter a lot when governments have bizarre laws that require spending public funds on it -- e.g. Seattle's SMC 20.32.030 "Funds for works of art" which states that "All requests for appropriations for construction projects from eligible funds shall include an amount equal to one (1) percent of the estimated cost of such project for works of art..."

Of course, the law doesn't even attempt to define what is and isn't "art". They leave that up to the Office of Arts and Cultural Affairs... and I'm sure those folks spend PLENTY of time (also at public expense) debating exactly that question.

I think that Public_Heretic and Eielizer are actually having a disagreement about the definition of the word "Category".

If Eliezer says that a Category is "a label applied to a set of words that describe things which are similar", Then he is correct to say that a Category is "Wrong" or "not a proper category" if the words contained in the set do not describe things which are similar.

If Public_Heretic defines a Category as "a label applied to a set of words that describe things", then he is correct in saying that there can be no wrong or false categories, so long as the label is applied to a set of words.

I'm sure they would both agree to the point that a label applied to a set of words that describe things which are similar is more useful than a label applied to a set of words that describes things which are not similar.

Maybe this is covered in another post, but I'm having trouble cramming this into my brain, and I want to make sure I get this straight:

Consider a thingspace. We can divide the thingspace into any number of partially-overlapping sets that don’t necessarily span the space. Each set is assigned a word, and the words are not unique.

Our job is to compress mental concepts in a lossy way into short messages to send between people, and we do so by referring to the words. Inferences drawn from the message have associated uncertanties that depended on the characteristics we believe members of the sets to have, word redundancy, etc.

In principle, we can draw whichever boundaries we like in thingspace (and, I suppose, they don’t need to be hard boundaries). But EY is saying that it’s wise to draw the boundaries in a way that "feels" right, which presumably means that the members have certain things in common. Then when we make inferences, the pdfs are sharply peaked (since we required that for set membership), and the calculation is simpler to do.

He also says that it’s possible to make a "mistake" in defining the sets. Does this result from the failure to be consistent in our definitions, a failure to assign uncertainties correctly, or a failure to define the sets in a wise way?

I think what I mean by "Aha, this the meaning of the word flooble" is: "I use the word flooble in everyday life, and I feel comfortable with it. But until now I've never been able to 'play Taboo' with it. Now I can give a substantive definition of how I use it. This will be useful if I need to unpack my utterances for other people (or, conceivably, computers). Also, when people near me in 'language space' use the word flooble, we can compare definitions and possibly dissolve arguments."

So "the meaning" here isn't a definition of the word (all must bow to the mighty power of the definition), but a location of my language along the 'flooble-meaning' axis. To put it another way, the meaning that we "feel" is the one in our (individual) heads. Of course the word has little power if you can't use it for communication --- although we shouldn't underestimate its use in the internal monologue.

In all this, I realise other people may be located at other places along the "meaning-meaning" axis, and mean something else by "Aha, this is the meaning of..." but Doug S., in the comment you link, says:

I've come up with what is, to me, a satisfactory definition of "art"...

which is a more unpacked version of "meaning" than I usually manage.

The second point I want to make is about words being "wrong" --- saying "fish" and meaning to include dolphins, for example.

In a sense, I'm using the top of the post to argue with the bottom of it.

Wondering how to define a word means you're looking at the problem the wrong way—searching for the mysterious essence of what is, in fact, a communication signal.

vs

You come up with a list of things that feel similar, and take a guess at why this is so. But when you finally discover what they really have in common, it may turn out that your guess was wrong. It may even turn out that your list was wrong.

We have two different uses of words here. Firstly, you have a communication signal, which means "When I say this word, I trust that it conjures a picture in your head which is broadly similar to mine." --- so, for example, you can say "go to the shops and get some fish" to your partner, and you know that they'll bring back, not just fish, but the right kind of fish --- or maybe the shop had no fish, so they got crab, or chicken. Of course, they wouldn't argue that they'd brought home fish, but the mental picture painted by the word was sufficient that you are happy with their purchase.

Secondly, you have an academic, informational label, which means "Things whose properties are generally correlated for some underlying reason, so that observations of a large set of these things carry evidence about all of these things." "Is a trout a fish? It has scales and gills, this is good evidence, so we'll accept that it's likely to be a fish. Therefore we guess that it lays eggs." Again, there is an underlying cultural assumption, but the scientific literature makes this explicit. We can actually test whether a dolphin is a (biological) fish, by looking at the properties written in the textbook.

These two uses of words are related, of course, but they are different. In the first case, all you can say about the "meaning" of the word is the dictionary-writer's approach --- roughly how are people using the word? Can we form a better indication of what they mean by it than a list? A use of the word can "fail" in the sense that the idea in the speaker's head hasn't been transmitted to the listener, but apportioning blame in this case is pretty pointless. If we must (in order to avoid the problem in the future, for example), I put the onus on the speaker to ensure that they use words which are appropriate to their current milieu and on the listener to use the milieu to interpret the words. If you have gone back in time and say "I eat fish" and someone presents you with unwanted dolphin-meat, that was your error. If they have come to the present (their future) and say "dolphins are my favourite fish", it's reasonable to update their vocabulary. In either case, adapting the outliers to the population is a reasonably low-cost way of doing business.

In the second use of a word, an authority really has defined the word to mean something, and a use of it can be "wrong" by not matching the definition. We can also ask "is the authority's definition helpful?" which I think is where you're going with "dolphins aren't fish, even if everyone thinks they are". If the textbooks define "fish" in such a way to include dolphins, and then we determine that dolphins don't fit into the same categories as other fish, it's worth taking them out of the category to avoid future confusion.

As a final remark, consider the use of the word "dairy [products]". A good way to start an argument is to ask if this classification includes eggs. (This is pertinent to me, since I'm allergic to both milk and eggs. I want to make sure people don't give me butter, so I say "no dairy products", and then I either say "or eggs" or "including eggs". Experience has shown that neither of these phrasings will avoid an argument.)

I propose a compromise. We take dolphins from the fish list, and justly exchange it with Python on the other list.

Greetings ! I am new to your blog. Some articles of yours are truly enlighting me. However, there are posts like this which I clearly don't understand the point made. The conclusion here is that you can be mistaken at categorizing things :

"Categorizing is a guessing endeavor, in which you can make mistakes; so it's wise to be able to admit, from a theoretical standpoint, that your definition-guesses can be "mistaken". "

Such conclusion is obvious and given in almost any of your articles about words I've read so far. So... what's the point here anyway? To my opinion, the article doesn't answer to the title at all, and I read it twice.

Overall, I feel a huge lack of clarity in many of your articles or perhaps it's just me but most of the time I don't get the big picture. I'd like to understand more of you because I see that sometimes your ideas are very interesting.

Can the author or any of his readers explain to me what is he truly trying to say about definitions on this article and others, more than just "defining words are hard" and such trivial stuff please? I would gladly read you.

PS1: " A Human's Guide to Words " is quiet an inapropriate title for such an obscure/unclear serial of articles about words.

PS : I apologize for my never-to-be-perfect english.

What is wrong (if you don't try to match the real biological taxonomy of Pisces) with definition like "vertebrate constantly living in water" for "fish"? While true_fish and dolphins have some differences, they have the very common points that led to the unification in the first place.

EDIT: Had already expanded upon by Scott Alexander.

I feel the need to address the python vs. modern art thing too - if you just compare the extensional list of art against the intensional definition, you'll see that modern arts pass as arts (at least sometimes) while python definitely doesn't. Modern arts involve some work, are intended to inspire aesthetic emotions, and often do in some people experiencing them. Python, while being an elegant tool, was not (probably) designed with the primary intention of producing emotions, but rather with the intention of being a convenient tool to code.

Also, there is a legitimate quest of finding the "right definition" of a word, as in what concept it represents. Even if there is no class corresponding to it in reality (e.g. God) the existence of the word means some people treat it as a meaningful concept. If enough people use the same word with enough gravitas, and you want to talk to them about it, you will need to understand what their common ground of the idea is. Even if, as with free will, you arrive at the conclusion that there is no common ground to speak of. Not as interesting as carving reality, perhaps, but if you are somewhat interested in what other humans think, it does have merit.

Turns out, fish don't even exist.

That fish list was a pretty good historical example but I can give you a current example: what is a continent?