Minimalist Program [...] A particular language L is an instantiation of the initial state of the cognitive system of the language faculty with options specified. We take L to be a generative procedure that constructs pairs (π, λ) that are interpreted at the articulatory-perceptual (A-P) and conceptual-intentional (C-I) interfaces, respectively, as "instruction" to the performance systems. π is a PF representation and λ an LF representation, each consisting of "legitimate objects" that can receive an interpretation (perhaps as gibberish). If a generated representation consists entirely of such objects, we say that it satisfied the condition of Full Interpretation (FI). A linguistic expression of L is at least a pair (π, λ) meeting the condition - and under minimalist assumptions, at most such a pair, meaning that there are no levels of linguistic structure apart from the two interface levels PF and LF; specifically, no levels of D-Structure or S-Structure. The language L determines a set of "derivations" (computations). A derivation "converges" at one of the interface levels if it yields a representation satisfying FI at this level, and "converges" if it converges at both interface levels, PF and LF; otherwise, it "crashes".
- Chomsky (1995), Pag. 219