On the Concept of "Fruitfulness" in Genetic Linguistics
Merritt Ruhlen


It has been asserted by critics that Greenberg did not prove the linguistic families that he posited in his work on linguistic taxonomy. Yet Greenberg never claimed to have proved anything, and pointed out on more than one occasion the the concept of "proof'" was not applicable to historical linguistics. Rather, he argued, one of the determining factors in the success or failure of genetic hypotheses was whether they were ``fruitful,'' that is, whether they were extended by further research or led to the solution of recalcitrant problems that had hitherto remained unsolved. I will show, with regard to my own work on the Amerind family, that certain hypotheses proposed in Language in the Americas have now been both extended and refined, and that unresolved problems in accepted families such as Algonquian may be solved by consideration of the larger Amerind context.