EXTENSION CONDITION

[mallu]

What is 'extension condition' within Minimalist context.I rember having read ' operations like merge and move will only apply to root syntactic objects'.That elicit another question what are root syntactic objects?,and why they are called so.
Can any one give a kind reply?

[mallu]

No extension to the post.Hope somebody would come out to help, djr or some other syntacticians?

[Daniel]

A tree has roots-- the lowest elements, or the lexical nodes. I think that's what it's referring to.
The Extension Condition appears to require that merge/move makes larger nodes than its input-- generating bigger trees, not smaller ones.

The Extension Condition is the requirement that grammatical operations enlarge the tree in the sense that the phrase marker that results from the operation contain as a sub-constituent the phrase marker that was input to the operation. (11) illustrates the condition.

http://www.blackwellpublishing.com/content/bpl_images/content_store/sample_chapter/9780631223603/hornstein.pdf

[vahid]

There are some conditions governing the basic syntactic operations of Move/Merge. These two operations extend the syntactic structures and they should follow the governing extention conditions.