[microtonal]

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.

[TeMPOraL]

> 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.