comparative method morris halle pointed phonological system could analyzed two phonemes seems clear two languages related could reconstruction done involving set correspondences among words morphemes comparative grammar fact phonology two phonemes would formal excersise real phonology reconstruction referring would validity unless languages really related case mixed languages unless relevant parts related formal possibility important following extent shows assume ability write comparative grammar either necessary sufficient showing languages question related ability write convincing comparative gramm r significant token language relatedness sjown establishing convincing set correspodences suitable sets words morphemes languages compared even conceded harder general convincing case comparative grammar case set correspondences since former would seem include latter plus lot one yet shown anywhere else way establish language relatedness writing complete comparative grammar even meillet conceded 1925 even demand fragment grammar perfectly wellestablished families either indeed done another matter 9and ultimately interesting one significant amount grammatical comparison though whole grammar offered nostratic theory find likely though perhaps yet established well amerind theory find basically unsupported karl victor example perhaps uninteresting illich svitych proposed write nostratic comparative grammar never much sapirpromised write one uto aztecan failed though fairness note sapir lived another two decades whereas illich svitych died without even finishing lexical morphemic comparisons bulk evidence public domain nostratic criticism sapir course agree need write comparatve grammar uto aztecan order everybody able see uto aztecan languages related need case nostratic 9and indeed given age proto nostratic language seems unlkikely ever partial grammar