Commentary by cpressey on Linguistics works
Essentials of English Grammar
English Transformational Grammar
Modern English Linguistics
Towards a Semantic Description of English
An Introduction to Unification-based Approaches to Grammar
The Language Complexity Game
CFG is in P but is not P-complete.
But CFG is not quite enough it seems.
CSG is PSPACE-complete. That's way too big.
It makes sense that evolutionarily there would be a tension between maximizing expressivity and minimizing complexity.
Thus, the mildly context-sensitive languages.
RCG is P-complete.