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This paper presents a detailed exploration of semantic proof nets and their application in the framework of Intuitionistic Linear Logic. We examine the role of determiners like "every" and "each" as linked to quantifiers and connectives, elaborating on their semantic representations through proof. Notably, we apply the contraction rule to illustrate how complex semantic structures can be derived from simple proofs in logical systems. The work emphasizes the importance of syntactic proof nets and their role in parsing linguistic structures, drawing connections between proof theory and semantic representation.
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Proof-nets and semantic applications Alain Lecomte ESSLLI2002
e+ t- e- t+ child Semantic proof nets • child x:e, child: et |- child(x) : t hence : child: et |- x.child(x):et
run : e+ t- x e- t+ x child
run : e+ t- x e- t+ x child
run : e+ t- x e- t+ x child
run : e+ t- x x e- t+ x child x.child(x)
run : e+ t- x x e- t+ x child x.child(x)
each, every… • A determiner like every, each… decomposes into : • A quantifier, for instance : type : (et)t • A connective, for instance : type : t(tt)
needs two predicates (e t) for obtaining one proposition (t) • A determiner is therefore of type (et)((et)t)
A determiner is therefore associated with a sequent: • Its « semantic » is represented by its proof
C deduction
remark • With a very remarkable step : an application of the contraction rule! • necessity of working inside Intuitionistic linear logic with exponentials • The exact sequent which encodes the determiner is : !e !e t ( t t ), ( !e t ) t ( t ) (( t ) t ) |-- --o --o --o --o --o --o --o --o
Representation of the proof c (!e –o t) –o ((!e –o t) –o t)
every child c child (!e –o t) –o t
every child likes to play c likes to play t child
Application - + + A A –o B +
Application A - B +
A + Abstraction B -
A + Abstraction B - B –o A +
Syntactic proof-nets • Proof-nets for Lambek calculus • Like PN for MILL + • condition on semi-planarity
every child plays 1) unfolding s+ np - s - np\s + np + (s/(np\s)) - n + s - n - child np\s - plays s + (s/(np\s))/n - every
every child plays 2) links s+ np - s - np\s + np + (s/(np\s)) - n + s - n - child np\s - plays s + (s/(np\s))/n - every
Attention! 2) links WRONG ! s+ np - s - np\s + np + (s/(np\s)) - n + s - n - child np\s - plays s + (s/(np\s))/n - every
Parsing • through homomorphism • H(s) = t • H(np) = !e • H(n) = !e –o t • H(A/B) = H(B\A) = H(B) –o H(A)
every child plays s+ np - s - np\s + np + (s/(np\s)) - n + s - n - child np\s - plays s + (s/(np\s))/n - every
every child plays 3) homomorphism t !e t !e –o t + !e (!e –o t) –o t !e –o t t !e –o t child !e –o t plays t+ (!e –o t) –o ((!e –o t) –ot)) every
semantic recipes • child : x.child(x) • every : P.Q.(x.(P(x)Q(x)) • plays : x.play(x)
d e+ t- !e- t+ child • represented by proof-nets :
e+ t- !e- t+ plays • represented by proof-nets : d
every c (!e –o t) –o ((!e –o t) –o t)
plugging lexical semantic types to the homomorphic PN by cut
d e+ t- !e- t+ child t !e t !e –o t + !e (!e –o t) –o t !e –o t t !e –o t child !e –o t plays t+ (!e –o t) –o ((!e –o t) –ot)) every CUT
t !e t !e –o t + !e t !e (!e –o t) –o t t !e –o t plays t+ (!e –o t) –o ((!e –o t) –ot)) every d child
d e+ t- !e- t+ plays t !e t !e –o t + !e t !e (!e –o t) –o t t !e –o t plays t+ (!e –o t) –o ((!e –o t) –ot)) every d child CUT
t !e d t !e –o t + !e t !e (!e –o t) –o t t plays t+ (!e –o t) –o ((!e –o t) –ot)) every d child
PNevery t !e d t !e –o t + !e t !e (!e –o t) –o t t plays t+ (!e –o t) –o ((!e –o t) –ot)) every d child CUT
d !e t c plays t+ d child
d !e t c plays t+ d child
d !e t c plays t+ d child
d !e t c plays x t+ d child
d !e t c plays x t+ d child
d !e t c plays x plays t+ d child
d !e t c plays x plays t+ d child child
d child(x) !e t c plays x plays t+ d child child
d plays(x) child(x) !e t c plays x plays t+ d child (x.((child(x),plays(x)))) child
Logical synthesis:from a formula to a sentence • the reverse story: • Start : • a semantic formula • + semantic recipes for lexical entries 1, 2, …n • Goal: • A sentence using all these recipes the meaning of which is
Usual solutions:-term unification ? s:kiss(p,m) Peter : np : p kisses : (np\s)/np: x.y.kiss(y,x) Mary : np : m GOAL
np+ s- kiss(,) np+ y.kiss(y, ) ? s:kiss(p,m) Peter : np- : p kisses : (np\s)/np: x.y.kiss(y,x) Mary : np- : m