I agree with the analyses of the sentence as an ellipsis. Ed V. notes
that this points up the usefulness of the generative approach to grammar
in which the sentence would be derived from two 'kernels'. The question
is, derived when, how, and by whom?

There are now non-derivational theories of grammar. Instead of proposing
derivations (which must proceed stepwise, and have thus caused a lot of
revision in generative theories), they propose always-present links
between structures with particular features in common.

In the case at hand, we have a common construction that looks like a
compound direct object, but the 'not' looks problematic: VERB X
(and/but) not Y . (the parentheses indicate that the 'and/but' is
optional.) This can exist as a sort of template in the grammar. The
template is connected to the full version of other predicate templates:
VERB X  ,  not VERB Y. Hence the meaning relationship is available from
the truncated sentence. How the connection gets set up is then the
interesting question.

Hey, here's a cool thing: try it the other way around, and the second
clause can't appear in truncated form:
'*I don't like apples, but/and peaches.' (although I can sometimes get
this to sound OK with just 'but peaches', for contexts in which 'I like
apples' is being contradicted.)
'I don't like apples, but/and I do like peaches.'

How about: 'It is apples I like, not peaches'?

By the way, I don't think linguists would classify 'not' as an adverb,
although that is the traditional-grammar classification (assigned, I
suppose, because it 'modifies verbs' and that's what adverbs do). They
would call it a negative marker. And does it modify the  verb, or the
whole clause? In logic, propositions are negated up front:

NOT I like apples.

If sentences have propositions as their meaning unit, then 'not' is a
clause-level modifier (something adverbs can also do).

We could go on and on. But we have work to do.

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Johanna Rubba   Assistant Professor, Linguistics
English Department, California Polytechnic State University
One Grand Avenue  • San Luis Obispo, CA 93407
Tel. (805)-756-2184  •  Fax: (805)-756-6374 • Dept. Phone.  756-259
• E-mail: [log in to unmask] •  Home page: http://www.calpoly.edu/~jrubba
                                       **
"Understanding is a lot like sex; it's got a practical purpose,
but that's not why people do it normally"  -            Frank  Oppenheimer
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