"I have gotten very involved in historical linguistics," he continued.
The techniques of comparison and analysis are called historical linguistics.
Historical linguistics has long wrestled with the idea of a single original language.
The second point, mass comparison, is controversial in historical linguistics.
Historical linguistics - study of language change over time.
However, evidence from historical linguistics cannot bridge the gap between those two periods.
In the biological field several software programs were then developed which could have application to historical linguistics.
He claimed this put African historical linguistics on a secure basis for the first time.
However this is a common problem in historical linguistics, and one which perhaps can be overcome with the use of the comparative method.
He is most famous today as a founder of modern comparative historical linguistics.