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by bobwaycott 3693 days ago
I'm not sure about the claim on implicit lack of parsing structure. I read your example as who did what, where, in what. There must be some level of structural parsing and recognition so we understand it was Alice who drove in a car, that the car is owned by Alice, and that she, Alice, drove down the street, in her car. That we automatically understand all this seems to indicate some level of implicit parsing, right? Admittedly, it's been many years since I did any study of linguistics and language acquisition, so I'm pretty ignorant of the current state of knowledge here. Am I just layering my grammatical parsing atop an existing understanding that doesn't parse at all?
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I think observing how children learn their native language is pretty informative. They can speak and understand it very well, whether or not they were taught formal grammar at school. Personally, I know very, very little of Polish grammar (i.e. of my native language), and only little bit more of English grammar - and that is only because foreign language courses are pretty heavily grammar-laden.

I'm not a linguist, but seeing how people a) can understand sentences that are grammatically malformed perfectly well, b) can easily derive meaning out of "sentences" stripped out of verbs ("I her dinner cinema Washington"), it seems to me that most of the work is being done by pattern-matching to known words and phrases. E.g. "drove down the street" is a kind of semantic unit on its own.

Again, I'm not a linguist, but a lot of introspection as well as observing other people strongly suggest to me that humans do anything but parsing grammatical structures.

It's precisely how strongly we conform to grammar, without having been taught it, which shows that it's key to our internal representations/to how we learn language.

Here is the undeniable proof that syntactic structure exists. Consider the sentence `The magician pointed at the man with the hat.' This is a perfectly natural sentence, of which there are two likely interpretations. One is that the magician used a hat to point at the man. The other is that the man who was pointed at wore a hat.

What distinguishes these sentences? Only the underlying syntactic structure, of whether to parse it as `the magician pointed at (the man) with the hat' or as `the magician pointed at (the man with the hat)'. This `hierarchical structure' of our sentences is syntactic structure at its essence.

You argue that humans can understand sentences with whatever grammar, and parsing is pretty much pattern-matching of words. But what about the sentence pair : `Benny chased Jenny' versus `Jenny chased Benny'? These have the same words, and mean different things. It is only our syntactic understanding of how words are ordered in English that allows us to understand these sentences.

Here is the undeniable proof that syntactic structure exists.

There are multiple hypothesis of what a sequence of words can mean, which is not the same thing as 'we form explicit syntax trees in our heads when reading a sentence'.

I could also give you the bag of words

magician point man hat

You would derive meaning from this bag of words, probably the same interpretations as in your example. However, the sentence is utterly ungrammatical. Note that I am not contending that we don't use some form of syntax at all. E.g., I think that someone whose native language has a freer word order than English will assign more hypotheses to the bag of words above (e.g., my brain also considers the less likely option that the magician is the object).

Another problematic aspect of this hypothesis is that a longer sentence will have so many possible parses that it would take a long time to construct and consider all parses. Moreover, I find it unlikely that we have thousands of exact syntax trees in our head that we compare.

> There are multiple hypothesis of what a sequence of words can mean, which is not the same thing as 'we form explicit syntax trees in our heads when reading a sentence'.

Yeah. I'm playing with a different idea now - maybe that "tree structure" that "undeniably exists" in our brains isn't an explicit syntax tree, but an artifact of recursive, adaptive pattern-matching? I.e. if you look at things like reading speed or "understanding" speed, you'll notice that people tend to process stuff in large blocks until something "does not click", and they have to focus and process the block in detail. That sort of feels like a recursive refinement, and any process that recurses in more than one place generates a tree structure as a side effect.

I'm not sure what you're implying. The fact that we are not consciously aware of parsing grammatical structures doesn't mean it doesn't happen.

For example we know for sure that the brain applies sophisticated mathematical algorithms to signals coming from the ears to locate sound in 3D space, yet we are certainly not consciously aware of it - we just "know" where the source is located

Regarding grammar, there is a theory called Universal Grammar from Chomsky that we are born with grammar structures in the brain.

Some recent news on it - http://www.medicaldaily.com/noam-chomskys-theory-universal-g...

Disclaimer: this very article was used by a linguistics professor of mine to show why not to trust the popular news reporting and look at the study.

It's a very good study, but does NOT prove `UG' once and for all.

Ah, sure. Those are excellent points. I wasn't really thinking about how we bridge grammatical incorrectness. For myself, perhaps because I'm a grammar nerd, I feel like I always parse someone's mistaken statements into their grammatically correct forms. But I can recognize doing that after I've already figured out what they were intending to say. Same happened with my kids. That's a helpful vector for thinking about the problem, for sure. Thanks!