Problems that a theory of linguistic change must answer.

Problems that a theory of linguistic change must answer.

1. The constraints problem

   • In what linguistic and social conditions are certain changes likely or unlikely?

2. The transition problem

   • What intervening stages "can be observed, or must be posited, between any two forms of a language defined for a language community at different times?

3. The embedding problem

   • How are changes embedded in the matrix of linguistic and extralinguistic concomitants of the forms in question?

4. The evaluation problem

   • How can the observed changes be evaluated - in terms of their effects upon linguistic structure, upon communicative efficiency, and on the wide range of nonrepresentational factors involved in speaking?

5. The actuation riddle

   • How and why do changes begin?