How do Syntax and Semantics Get Along?
Friday, May 2nd, 2008Jere Mitchum dropped us this note Monday:
“I’ve been concerned about the awkward placement of only in present day writing. This example is from your April 27th discussion of denouement:
‘It has only been in the language since the latter half of the 18th century, so it has changed little.’
It seems to me that only should be next to since because the sentence means it has been in the language only since the latter half of the 18th century.”
“Another recent example may be clearer: ‘We were only able to book six travelers.’
Only here modifies six, not able. Why not place it next to the word it modifies?”
My response to Jere was so long that I haven’t heard from him since. The reason I was swept away in my answer to this question is that it touches on one of the most fascinating aspects of language: how it is processed by the human brain.
In fact, language comprises several layers of mental rules that operate independently but simultaneously. The semantic regions in our brains feed on syntactic and morphological (word form) regions but maintain their own set of rules and acceptable relationships.
This means that the semantic operations of our minds put the semantic components of a sentence together in a way vastly different from the way syntatic rules put words together. The classic example is, “An occasional sailor walked by.” I think most English speakers would accept this sentence even though ”an occasional sailor” here does not refer to someone who occasionally sails.
Even though the adjective occasional is perfectly at home before the noun sailor syntactically, its meaning does not combine sensibly with sailor in this sentence. So, the semantic component in our brains simply looks and finds another word in the sentence whose meaning the adjective makes sense with, and we understand the sentence as quickly as we would have had syntax placed occasionally before walked.
I have published quite a bit of scholarship about noun phrases like criminal lawyer and old friend. A lawyer doesn’t have to be crimnal to practice criminal law (though some wag might suggest it would help). Again here, the semantic rules dig into the syntactic stuff of this phrase and decide that the suffix -(y)er has more likely been added to the phrase criminal law than simply to law. Piece of cake.
While an old friend may be old, the semantic operator in our brains is happy if only the friendship is old. The definition of friend is “member of a friendship” so, at the semantic level, old may modify either main semantic concept: “old member” or “old friendship”. Semantics operates on semantic objects, not syntactic or morphological ones. Makes sense.
The syntactic component of our mind ’reads’ morphological rules, and follows hints laid down by suffixes and the like: occasional goes well with sailor but three does not, since adjectives may modify nouns syntactically but numbers above one require a plural noun. This information helps semantics but doesn’t do its job for it.
The semantic component in our minds operates on logic: which words make sense together? Semantics looks for the most likely combinations whether the syntactic construction helps or not. Semantics considers syntactic rules suggestions, not laws.
I find it fascinating that we can collect examples like these prove that our brain contains a language processor that comprises distinct parts (levels, subcomponents) that talk to each other but have their own rule-governed characters. Linguists today are exploring the interactions between these parts and the discoveries they are making are truly remarkable.


