10. The rhythmic interpretation of Parisian organum.
One of the most basic problem complexes, and one which is most intimately connected with the above considerations of structure, involves the rhythmic interpretation of Leonine organum. For this, Johannes de Garlandia (also, later, Franco of Cologne and Anonymous IV) gave the so-called law of consonance. This states that consonances (octave, unison, 5th, 4th, 3rd) are long, the other intervals short, and currentes equally fast where possible. The question then arises: can this law be evaluated as being based on older tradition (i.e. corresponding with ‘historical’ data, bearing in mind that Garlandia was writing two generations later)? Or is it, conversely, to be regarded as a retrospective attempt to minimize the differences between organum per se and copula, a calculated interpretation after the event? Eggebrecht (1960, p.60) would adopt the latter view. At any rate, the law of consonance hardly seems practicable if the formulation that has survived is rigidly applied: it should probably be narrowed down so that only structurally important consonances are interpreted as longs, as Reckow has done (Anonymous IV, 1967, ii, p.80ff).
One argument which is usually adduced in the problem of rhythm, and which is also secretly at work here, is that organum purum should be in totally free rhythm, or ‘Gregorian, in equal (or nearly equal) values’. Either this wrongly implies an interpretation of plainchant in completely equal note values, or else it is irresponsibly imprecise, to say the least. Rather, let us reflect that each phrase operated with points of emphasis and longs, and also that the distinction ‘non-modal’/‘modal’ should not automatically be equated with ‘not susceptible to rational interpretation’/‘measurable in a rational way’. It then begins to seem more credible for the concordance law to be a throwback to an earlier tradition. One might argue also that the values ‘long’ and ‘short’ might not have been fixed proportionally, but might have been relative concepts, i.e. ‘longer than short’, ‘shorter than long’. Finally, however the law might originally have been formulated, in both discant and organum pieces it would naturally have resulted in a rhythm generally similar to the so-called 1st mode. So here as well we may have one of the lines of development which, in the second half of the 12th century, led to the principal of modal rhythm (ex.11, last phrase).
In certain circumstances, therefore, the above factors (and others to be considered below) might directly have affected the melodic structure of the ‘classical organum’, without mediating influences from discant composition.
11. Organum of the 13th century and later.
Judging by the extant sources, the non-modal sustained-note style lasted for only a limited time and on a small scale. At any rate, the surviving versions of the Magnus liber are witness both to the obvious climax of organum composition and to its relatively swift fall from a favoured position in the centre of musical development after the appearance of modal rhythm. This quickly gained a hold on and modified all musical forms of the period. With it arose quite new forms and possibilities (such as three- and four-part music) important for the future. In the field of two-voice plainchant settings it first affected the upper voice the more noticeably. This was for structural reasons, and perhaps also because the inviolability of the sacred tenor was still respected. Only after this were the tenor parts affected.
In the 13th century, however, all polyphony that was not in modal or mensural rhythm soon came to be regarded as unsatisfactory. Organum too was seen in this light, and was finally actually rewritten. It is only in the sense of a 13th-century interpretation that a transcription such as that of Waite (III(3)1954) can be justified. Waite saw the Magnus liber as a work wholly in modal rhythm. His interpretation may correspond to the time from which the sources date, but cannot satisfy the attempt to come closer to the work’s original rhythmic style. This situation corresponds with what Franco (c1280) said: he contrasted all polyphony, as being musica mensurabilis, with monophonic plainchant, musica plana. He subsumed Garlandia’s concepts of organum per se and copula under a new notion, organum purum, and defined copula anew. Thus, as in the 12th century, but on a new level, the only distinction made was between sustained-note and note-for-note composition. However, this time the future lay in the hands of the note-for-note style, and this was the case away from the centre of musical development as well.
Apart from the interpretation of older compositions mentioned above, the sustained-note style played a specific role in the 13th century only in the field of three- and four-part compositions. Yet here the upper parts were necessarily joined one above the other in modal rhythm. To a certain extent, they formed their own discant among themselves. For this reason the expression ‘copula’ was not used for this phenomenon. Similarly, Anonymous IV called plainchant settings for more than two voices simply ‘triplum’ and ‘quadruplum’, according to the number of parts, omitting the generic term ‘organum’. Together with the parallel formulation organum duplum, this meant that the word ‘organum’ could continue to stand (as it did in the 12th century) as a general term for polyphony based on plainchant (Ger. Choralbearbeitung); this was in contrast with the conductus, which was independent of plainchant. Thus an actual method of performing liturgical chant became an expression signifying the technique of composition itself. And now, once again through common practice, the word came to mean a musical form and genre.
In areas adjacent to France, away from the centre of these developments, matters stood differently. Apart from the peripheral, partly derivative tradition, particularly that of England (the Notre Dame manuscript D-W 677 is probably of insular origin), and excepting a few, easily identified, borrowings of individual pieces, the French 12th-century development of organum was not copied or adopted. In England it is rather the case that there were special traditions of improvised and composed discant. In Spain there were more influential contacts with France.
In Germany, however, polyphonic practices that invariably corresponded to pre-12th-century French developments did not arise until the 13th century. This late start was compensated by an existence lingering into the 16th century (see Geering, 1952). It was occasioned by the persistence of the technique of doubling a given cantus, which produces not genuine but only apparent polyphony, and other primitive techniques.
Without doubt this was not a simple case of meaningless and outmoded customs in cultural backwaters. It could also be a vital, albeit tradition-based practice, in definite cultural layers and for specific purposes, co-existing with the more universal developments. It is a phenomenon rather like the similarities between early German organ music of the 15th century and French organum, to which scholars have frequently drawn attention. Here, according to Göllner (XI1961), are found the same elementary ideas of doubling displayed instrumentally. Admittedly, the full potential of these ideas was not to be felt historically until a later period, with the perfection of an autonomous instrumental musical art.
See alsoDiaphonia, and Discant, §I.
For bibliography see Organum and discant: bibliography.