The term analogy is used in a number of different senses and it is essential to distinguish these carefully. Proportional analogy and analogical levelling are the two main types and the largest number of forms in the history of English have been affected by their operation.

PROPORTIONAL ANALOGY

This kind of analogy can be summarised as a change on the basis of the following formula.

A  :

B

::

C  :

D

(A is to B as C is to D)

This can be seen working in the occasional change of weak to strong verbs, a change which is attested in varieties of southern American English and in first language acquisition (1) and is attested in cases of shift of conjugational type in the history of English (2).

1)	A: sing	B: sang	C: bring	D: brang (for brought)
2)	A: teach	B: taught	C: catch	D: catched > caught

The spread of umlaut in the history of German shows a similar operation of analogical change.

A  Haus

:   B  Häuser

: :

C  Baum

:  D  Bäume (for Bauma)

ANALOGICAL LEVELLING

The second sense in which analogy is used is ‘spread of a dominant pattern’, or in single cases, ‘change under the influence of another form’. The latter process can be seen in the phonetic adaption of words on the basis of semantic similarity as with the following French loans after they were borrowed in the Middle English period (this kind of change is sometimes labelled contamination).

The spread of a dominant pattern frequently involves a levelling of phonological contrast in order to attain paradigmatic regularity. This type of analogy only occurs after a certain change has become unproductive in a language. An example of this can be taken from the development of plural types in English. In Old English there were various plural patterns, some of which survived into the Middle English period. Of these the nasal plurals lasted a considerable time but were finally replaced by the s-plural, e.g. eye has the plural eyen in Chaucer but later shows a final s. Here the s, as the dominant plural suffix in the history of English, came to replace the nasal which is nowadays only present in English in ox : oxen as well as in children and brethren.

The key point with this kind of analogy is that variation in a paradigm is lost in order to create regularity. Another instance is the operation of Verner’s Law in Germanic which along with rhotacism has meant that historically there was an alternation of /s/ and /r/ in many verb paradigms. This has been levelled in English and German, but with a different sound chosen in each language. German has levelled to /r/ and English to /s/ (later voiced to /z/ due to intervocalic position). Hence one has verlieren (with /r/ everywhere) and lose (with /z/ from /s/ everywhere).

The common ground for both meanings of analogy discussed here is the creation of symmetry. This would seem to suggest that speakers value symmetry in some non-concrete way, not determined by environment, and that their knowledge of language and its possible forms includes the concept of system symmetry.

ANALOGICAL MAINTENANCE

In general /w/ after /s/ and before /o/ is lost in English. However, in those cases where the /w/ is present elsewhere in a word’s paradigm this may exert pressure to maintain it. Hence sword has lost the /w/ but swore /swɔə/ has retained the /w/ because this occurs quite normally in the present tense: swear /swɛə/.

ANALOGICAL CREATION

Again here one form acts as a model for another. In this instance, however, it is not a re-arrangment of an already existing form which occurs but a new word is created on the basis of another. Moonscape modelled on landscape is a good example. Regardless > irregardless on the basis of irrespective would be another case.

SALIENCE AND PRODUCTIVITY

The dominant pattern for any series of alternations can be called a productive pattern. This raises the question of why a given alternation or ending should come to be favoured by speakers. Take the example of the change from /θ/ to /s/ in the third person singular verb inflection as with hath < has. Why should {S} be favoured here? One good reason is that the alveolar fricative is phonetically more salient than the ambi-dental fricative.

This notion of salience can be invoked in the development of plural patterns in English. In Old English r-plurals occurred; some of these were replaced by nasal plurals and later virtually all were replaced by the s-plural type. This progression illustrates an increase in phonetic salience for the plural ending. The transition from r-plural to nasal plural type can be seen in the plural of child which is formally a double plural, containing both /r/ and /n/: childer + en > children. The dominance of /s/ over /r/ can be illustrated with an example from Low German: Kinners (the equivalent of Kinder 'children') contains both the r-plural ending /-er/ and the phonetically more salient /s/ plural.

The issue of analogy is discussed in many books on language change such as the following two:

Campbell, Lyle 2021. Historical linguistics. An introduction. Fourth edition. Edinburgh: Edinburgh University Press.

McMahon, April 1994. Understanding language change. Cambridge: University Press.