Language, stratification of, [63].
—— origin of, [67].
—— universal, [67].
—— English, 100,000 words in, [68].
—— classification of, [72].
—— made by convention, [73].
—— three conditions of, [78].
—— RR for 1st stage, [79].
—— R + ρ for 2d stage, [79].
—— ρ for 3d stage, [79].