August Schleicher

August Schleicher (1821–1868) was a German linguist who advanced comparative Indo-European studies and represented language relationships with a branching family tree.

Comparative linguistics: The systematic comparison of languages to establish their historical relationships and reconstruct earlier forms. This was the method underlying Schleicher’s comparisons of Indo-European languages.
Family tree model: A branching representation of languages descended from a shared ancestor. Schleicher made this model a prominent way to depict relationships among languages.
Franz Bopp: A German linguist who helped establish comparative Indo-European grammar in the nineteenth century. Bopp’s comparative grammar preceded and helped establish the research tradition Schleicher extended.
Wave model: A model in which linguistic innovations spread across neighboring languages in overlapping waves. It captures contact and overlapping change that a strictly branching family tree can miss.
Indo-European languages: A language family whose branches include Germanic, Romance, Indo-Iranian, Celtic, and Greek. Schleicher sought to reconstruct and classify this family’s earlier stages.
Schleicher's fable: A short reconstructed Proto-Indo-European text composed by August Schleicher. He used the fable to demonstrate how a reconstructed ancestral language might have sounded.
Jacob Grimm: A German philologist and folklorist who formulated a major account of consonant change in Germanic languages. Grimm’s sound correspondences supplied evidence for historical comparison in Schleicher’s era.
Neogrammarian hypothesis: The claim that sound changes operate regularly across a language, subject to identifiable conditions. This later principle sharpened historical explanation beyond Schleicher’s broader biological analogies.
Proto-Indo-European language: The reconstructed prehistoric ancestor of the Indo-European language family. Schleicher used comparative evidence to propose a systematic reconstruction of this ancestor.
Language divergence: The process by which related languages develop distinct forms and become less mutually intelligible. Branching descent in Schleicher’s model represents languages diverging from common ancestors.

Linked from 10 pages