Since there is a series of categories of phonetic environments such as accent, position within the syllable, nature of the directly following sound, of the directly preceding one, or of the one after the following one, etc., in every single case a complex of conditions becomes evident. If we compare the complexes of conditions of all cases with one another, we shall find that each one is different from the other […] Therefore, at best a notion of partial equality of the complexes of conditions can be considered relevant. (p. 53)
- Schuchardt (1972)