I am trying to figure out the right way to correctly process verbs in a logic engine. I’m trying to see if it just so happens that the way the ERG builds these trees makes things easier for me.
It will be way easier for me to process verbs if there is a way to walk a properly solved MRS scope tree, processing nodes as I go, such that, by the time I get to the verb, all of the variables it takes as arguments have been given their final values by the predicates and quantifiers I have already visited. Said another way: I’d love it if the variables a verb sees are never changed elsewhere in the tree after it is executed.
Right now I walk the tree by starting at the top predication and processing it:
- if it is not a quantifier (like _cave_n_1) it just does “the right thing” to the set of things in the variables that are its arguments
- If it is a quantifier, it:
- follows the tree exhaustively through the RSTR subtree first (executing as it goes)
- and then the body subtree
- and then potentially does some quantification on whatever happened
So if I generate a tree for “go to a cave slowly”, I’d get a tree like this:
TOP:h0┐ │ ┌_cave_n_1:x9 └_a_q:x9,h11,h12┤ │ ┌pron:x3 └pronoun_q:x3,h5,h6┤ │ ┌_to_p_dir:e8,e2,x9 └and┤ ├_slow_a_1:e14,e2 └_go_v_1:e2,x3
And I’d execute it in this order:
- _a_q (potential final qualification steps)
Which would work great, if I can always assume that the verb is always in a position where all its arguments have been evaluated like that example.
So, I think I’m asking if is it true that, in MRS solution trees:
- verbs are always a “leaf” of a scope tree (i.e. they never have “scopal arguments”, aka they can’t have children)
- verbs can never be in a subtree of a quantifier’s RSTR argument. Or, if they are, none of their variables are referenced in the BODY subtree
I hope this makes sense. I don’t understand enough yet about the grammar to know what forms I can expect where in the tree…