Do words have definitions?

Defining a word is notoriously difficult. Try to explain the difference between hatred and enmity, or define chair in such a way that includes bean bag chairs but excludes stools.

This is an annoyance for lexicographers and a real headache for philosophers and psychologists. Several centuries ago, British philosophers like Hobbes worked out what seemed like a very reasonable theory that explained human knowledge and how we acquire it. However, this system is based on the idea that all words can be defined in terms of other words, except for a few basic words (like blue) which are defined in terms of sensations.

This difficulty led at least one well-known philosopher, Jerry Fodor, to declare that words cannot be defined in terms of other words because word meaning does not decompose into parts the way a motorcycle can be disassembled and reassembled. You can’t define chair as an artifact with legs and a back created for sitting in because chair is not a sum of its parts. The problem with this theory is that it makes learning impossible. Fodor readily acknowledges that if he is correct, babies must be born with the concept airplane and video tape, and in fact all babies who have ever been born were born with every concept that ever has or ever will exist.

This seems unlikely, but Fodor is taken seriously partly because his arguments against definitions have been pretty convincing.

Ray Jackendoff, a linguist at Tufts University, argued in his recent Foundations of Knowledge, that words do in fact have definitions. However, those definitions themselves are not made up of words composed into sentences.

Observing (correctly) that one usually cannot find airtight definitions that work all of the time, Fodor concludes that word meanings cannot be decomposed. However, his notion of definition is the standard dictionary sort: a phrase that elucidates a word meaning. So what he has actually shown is that word meanings cannot be built by combining other word meanings, using the principles that also combine words into phrases. (p. 335)

That is, there are ways that words can be combined in sentences to achieve meaning that is greater than the sum of the meanings of the words (compare dog bites man to man bites dog). This is called phrasal semantics. Although linguists still haven’t worked out all the rules of phrasal semantics, we know that there are rules, and that these allow for certain combinations and not others.

Jackendoff has proposed that a very different system (lexical semantics) using different rules is employed when we learn the meanings of new words by combining little bits of meaning (that themselves may not map directly on to any words).

I think that this is a very attractive theory, in that it explains why definitions have been so hard to formulate: we were using phrasal semantics, which is just not equipped for the task. However, he hasn’t yet proven that words do have definitions in terms of lexical semantics. He has the sketch of a theory, but it’s not yet complete.

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57 thoughts on “Do words have definitions?”

  1. Gottleib Frege … groundbreaking work in linguistics.

    No way. He and others you quote are nobodies in linguistics. Why is it that you try to assume your own pet theorists (who, by the way, have a very mistaken view on linguistics) are anything at all in linguistics?

  2. No. Language is not about “communication and getting your point across” unless you define these terms so that virtually everything you say is “communication and getting your point across” at which point the whole argument becomes rather silly.

  3. “I move…”:

    How large a back counts? If you take a stool (3 tall legs) and put a very, very low back on it just 1 inch tall, is it a chair? What if the back is 2 inches? 3 inches? 2 feet? At what point does it become a chair?

    Or take a typical dining room chair. Cut off the legs and rearrange them so that it only has 3 legs. Is it a stool?

    This is a difficult problem that has been debated by philosophers for thousands of years. If anybody writing comments to this blog has an answer, they are guaranteed to become as famous as Aristotle (and perhaps win a Nobel prize. Yes, they don’t give Novel prizes for philosophy officially, but sometimes they cheat, cf Bertrand Russel).

    Please try my web-based experiments

  4. I believe that this entire blog post is comparable to asking for a definition of car that includes helicopter but excludes jet: utter nonsense. All 3 are vehicles and none of them are the same.

    I move that bean bags are neither chairs nor stools, but rather are within the same category. All 3 are seats. A chair has a back while a stool does not. Others have noted this same point. A quick check of confirms that this is correct.

    If bloggers spent more time thinking and reading prior to writing then fewer people would waste time reading nonsense of the attitude “I have a misinformed opinion, therefore you should listen to me.”

  5. Your conclusion is impressive. I only had to change one reference from it so that your perception could be better intepreted by me:

    “The reason why we are able to have a written and verbal language is not because of any sort of ingrained understanding or even specific knowledge. It is because we all have very similar sensory capabilities, and although we don’t always interpret things the same, or create each thing we see in exactitude, we do have sufficient numbers of commonality to reference which allow others to interpret what we perceive into something they can understand.”


  6. I have noticed, from reading these posts that people tend to use different prepositions when referring to “chairs” and “stools”.

    Therefore, I propose that a “chair” is something which you sit “in”, and a stool is something that you sit “on”.

  7. A stool is a chair of a specific type.
    kind of like a brand name it performs the same functions but generally adapted to a different situation.
    Then again, withe huge variety of chair now can we really say chair is a sufficient word there is something very different to me between a plastic round chair on a metal bar in a bus and an lazy-boy.

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