README⤓ .txt 2026-07-17T121634.146 000000000000760 Logics that drop the structural rule of exchange, so that the order of hypotheses is significant and cannot be permuted. Implication splits into two directed forms—one seeking its argument on the left, one on the right—and the resulting calculi are non-commutative.
Categorial Grammar⤓ .md 2026-07-17T120407.600 000000000000880 Ajdukiewicz (1935), Bar-Hillel, Lambek. Categories and slashes. Function-argument structure. Syntax as logic. Foundation of type-logical grammar.
Displacement Calculus⤓ .md 2026-07-15T074042.000 000000000012872 Morrill (2010). Discontinuity in Lambek. Intercalation and wrap. String-tuple semantics. Foundation for discontinuous constituency.
Full Lambek Calculus⤓ .md 2026-07-15T235854.000 000000000035992 Lambek's syntactic calculus (1958) supplies the residuated core; the additives and constants were added and the family systematized by Ono and Komori (1985) and Ono (1993, 2003). Galatos, Jipsen, Kowalski, and Ono, Residuated Lattices: An Algebraic Glimpse at Substructural Logics (2007), is the standard reference and the reason FL is the base of the field rather than one system in it.
Lambek Calculus⤓ .md 2026-07-15T065420.000 000000000015560 Joachim Lambek (1958). Syntactic calculus for categorial grammar. Non-commutative residuated structure. Types as syntactic categories. Foundation for type-logical grammar.
Lambek-Grishin⤓ .md 2026-07-15T074038.000 000000000013160 Grishin (1983), Moortgat and Kurtonina. Symmetric Lambek. Both products and coproducts. Interaction principles. Foundation for symmetric categorial grammar.
Non-commutative Logic⤓ .md 2026-07-15T064405.000 000000000015648 Lambek calculus (1958) for linguistics. Non-commutative linear logic (Abrusci 1991). Order of hypotheses matters. Models syntactic structure. Foundation for categorial grammar.
Ordered Logic⤓ .md 2026-07-15T060504.000 000000000019296 Ordered (non-commutative) logic from Lambek calculus (1958) and later work. No exchange rule: order of hypotheses matters. Models resource order, linguistic word order. Part of substructural logic family. Categorical: non-symmetric monoidal categories.
Pregroup Grammar⤓ .md 2026-07-17T120407.600 000000000000832 Joachim Lambek (1999, 2008), a later reformulation of his 1958 syntactic calculus. Replaces the residuated (implicational) structure of the Lambek calculus with a pregroup: an ordered monoid with left and right adjoints. A non-commutative, order-based type logic for natural-language syntax.
CRITERIA⤓ .txt 2026-07-17T120407.600 000000000000776 Not sufficient: Dropping weakening or contraction while keeping exchange (Linear, Affine, Relevant). A commutative substructural base.