Johannes Schmidt (July 29, 1843 - July 4, 1901) was a Germanlinguist. He developed the Wellentheorie (wave-theory) in linguistics to describe language development .
Johannes Schmidt was born in Prenzlau (Kingdom of Prussia). He studied Indo-European-, especially Slavic languages as a pupil of August Schleicher and received a doctorate in 1865. From 1866 he spent two years as a professor at a gymnasium in Berlin. Then he received a call from the university of Bonn to the position of an ordinary professor of German and Slavic languages. During his professorship in Bonn he published the well known Wellentheorie (wave-theory) in his book Die Verwandtschaftsverhältnisse der indogermanischen Sprachen (The relationships of the Indo-European languages). According to this theory new features of a language spread from a certain point in continuously weakening concentric circles, similar to the waves created when a stone is thrown into a body of water. This should lead to convergence amongst dissimilar languages. His wave-theory was directed against the doctrine of sound-laws introduced by the Neogrammarians in 1870. After about five years in Bonn he spent three years in Austria at the university of Graz until he received an offer to return to his own land. From 1876 he was living and working in Berlin (Kingdom of Prussia), where he became the leading head of linguistics at the Humboldt University. He died in age of 56 in Berlin.
Bibliography
Zur Geschichte des indogermanischen Vocalismus (Part I). Weimar, H. Böhlau (1871)
Die Verwandtschaftsverhältnisse der indogermanischen Sprachen. Weimar, H. Böhlau (1872)
Zur Geschichte des indogermanischen Vocalismus (Part II). Weimar, H. Böhlau (1875)
Die Pluralbildungen der indogermanischen Neutra. Weimar, H. Böhlau (1889)
Kritik der Sonantentheorie. Eine sprachwissenschaftliche Untersuchung. Weimar, H. Böhlau (1895)
Synchronic vs Diachronic: Synchronic (descriptive) linguistics is concerned with the form of a language at a given moment; diachronic (historical) linguistics studies the changes that occurred in a language or family of languages over time.
Applications of computational linguistics in machine translation, computer-assisted translation, and natural language processing are extremely fruitful areas of applied linguistics which have come to the forefront in recent years with increasing computing power.
Sociolinguistics, anthropological linguistics, and linguistic anthropology are social sciences that consider the interactions between linguistics and society as a whole.