(Lat.).
A
term first used by Guido of Arezzo for the relationship between
certain tones in the medieval gamut, specifically between a modal final and a
tone a fifth above or a fourth below (sometimes referred to as the affinalis);
specifically, each pair of tones, such as d and a, share a
particular pattern of surrounding tones and semitones within the six-note
diatonic segments c–a and g–e'. This concept was
recognized earlier, though not as systematically, by Hucbald and the authors of
Musica enchiriadis and Scolica enchiriadis (who used the term socialitas)
and by the anonymous author of the Dialogus de musica (who used similitudo).
By recognizing this feature of their gamut, theorists were able to reconcile an
inherited chant repertory with the eight-mode system. Specifically, it allowed
them to preserve chants with aberrant tones by notating them at the position of
the affinalis, where the same tone–semitone arrangement prevails; for
example, a first-mode chant with a B
(theoretically non-existent) could be notated at the a
position where B
becomes f. The medieval concept of transposition is essentially tied to the
concept of affinitas, based on tones sharing a particular core interval
pattern, rather than to a scalar concept. Affinitas provided the basis
for discussions of hexachords and coniunctae from the 13th century to
the 15th, and continued to be mentioned even after the rise of octave species
theory in the early 16th century.
See also Mode, §§II–III, and Theory, theorists.
D. Pesce: The Affinities and Medieval Transposition (Bloomington, IN, 1987)
D. Pesce, ed. and trans.: Guido d'Arezzo's ‘Regule rithmice’, ‘Prologus in antiphonarium’, and ‘Epistola ad Michahelem’ (Ottawa, ON, 1999)
DOLORES PESCE