An important goal of ntodent linguistic theory is to characterize as narrowly as possible the class of natural !anguaooes. An adequate linguistic theory should be broad enough to cover observed variation iu human languages, and yet narrow enough to account for what might be dubbed "cognitive demands" -- among these, perhaps, the demands of lcarnability and pars,ability. If cognitive demands are to carry any real theoretical weight, then presumably a language may be a (theoretically) pos~ible human language, and yet be "inaccessible" because it is not leanmble or pa~able. .
