The
monogenetic theory posits a single origin of all of the world's oral languages and it is the most accepted theory. It states that all current languages have formed through
language change from a single tongue that gradually differentiated into
mutually unintelligible languages. The first scholar to publish this theory was
Alfredo Trombetti, in the book ''L'Unità d'origine del linguaggio'', published in 1905. More recently,
Joseph Greenberg and
Merritt Ruhlen, proponents of monogenesis, argue that in modern languages there is sufficient evidence to reconstruct part of the
original language (called Proto-World or Proto-Sapiens). However, this claim has been highly controversial and the reconstructions made by Ruhlen are often discredited by mainstream linguists. Some studies seemed to correlate genetic and phonemic diversity, but this approach has been criticized thoroughly. Some proponents of monogenesis are
Alfredo Trombetti,
Joseph Greenberg,
Harold C. Fleming,
Merritt Ruhlen and
John Bengtson.
History The first serious scientific attempt to establish the reality of monogenesis was that of
Alfredo Trombetti, in his book ''L'unità d'origine del linguaggio'', published in 1905. Trombetti estimated that the common ancestor of existing languages had been spoken between 100,000 and 200,000 years ago. In the 1950s,
Morris Swadesh was one of the most important supporters of monogenesis. In the second half of the 20th century,
Joseph Greenberg produced a series of controversial large-scale classifications of the world's languages. Although Greenberg did not produce an explicit argument for monogenesis, all of his classification work was geared toward this end. As he stated, "The ultimate goal is a comprehensive classification of what is very likely a single language family." == Polygenesis ==