Editing Sound change (section)

==Principles==

The following statements are used as heuristics in formulating sound changes as understood within the [[Neogrammarian]] model. However, for modern linguistics, they are not taken as inviolable rules but are seen as guidelines.

'''Sound change has no memory''': Sound change does not discriminate between the sources of a sound. If a previous sound change causes X,Y > Y (features X and Y merge as Y), a new one cannot affect only an original X.

'''Sound change ignores grammar''': A sound change can have only phonological constraints, like X > Z in [[stress (linguistics)|unstressed]] [[syllables]]. For example, it cannot affect only [[adjective]]s. The only exception is that a sound change may recognise word boundaries, even when they are unindicated by [[prosody (linguistics)|prosodic]] clues. Also, sound changes may be [[regularization (linguistics)|regularized]] in [[inflectional paradigm|inflectional paradigms]] (such as verbal inflection), when it is no longer [[phonology|phonological]] but [[morphology (linguistics)|morphological]] in nature.<ref>See Hill, Nathan W. (2014) '[http://eprints.soas.ac.uk/18595/ Grammatically conditioned sound change].' ''Language and Linguistics Compass,'' 8 (6). pp. 211-229.</ref>

'''Sound change is exceptionless''': If a sound change can happen at a place, it will affect all sounds that meet the criteria for change. Apparent exceptions are possible because of [[analogy]] and other regularization processes, another sound change, or an unrecognized conditioning factor. That is the traditional view expressed by the Neogrammarians. In the past decades, however, it has been shown{{by whom?|date=May 2024}} that sound change does not necessarily affect all possible words.{{Citation needed|date=July 2021}} However, when a sound change is initiated, it often eventually expands to the whole [[lexicon]]. For example, the [[Spanish language|Spanish]] fronting of the [[Vulgar Latin]] [g] ([[voiced velar stop]]) before [i e ɛ] seems to have reached every possible word. By contrast, the voicing of word-initial Latin [k] to [g] occurred in ''colaphus'' > ''golpe'' and ''cattus'' > ''gato'' but not in ''canna'' > ''caña''. See also [[lexical diffusion]].

'''Sound change is inevitable''': All languages vary from place to place and time to time, and neither writing nor media prevents that change.