We shouldn't use English as a reference for language implementation. Almost nothing is self-evident.
"Between Baltimore and Boston, which is your favorite city?"
- you have two enumerated options, select one or the other
- you have a geographical area bounded by only two non-exact endpoints. Many would agree that New York City is in this range. Is Philadelphia? Is Harrisburg? Is Chicago? How far east-west can be assumed from north-south endpoints?
Granted this is a stretch for the discussion of "between" since it isn't intended to work with spatial data types, but it does illustrate the context-dependency of English.
The beauty of _Structured_ Query Language is that there should be no ambiguity.
here's another example of the difficulty of language from a discussion of AI:
"I like to eat pizza with sausage"
"I like to eat pizza with a fork"
"I like to eat pizza with a friend"
A meaning of 'with' that works for one of those sentences leads to confusion for the other two.