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Philosophia closes the first book with poetic lines that turn to nature imagery to continue the theme explored in the previous prose passage, namely the need to remove the darkness of false ideas to restore the prisoner to the true light. Just as stars are clouded over and water is muddied in a storm, so Boethius is instructed to cast out emotions to free his mind in order to perceive the truth. The metrumis composed of Adonics, i.e. ˉ ̆ ̆ ˉ x.
Two substantially different melodies for this metrum were recorded in the Cambridge leaf, one over the main text and one that is now truncated in the margin. The interlinear notation corresponds in its observable principles with the five other surviving notations for this song, which consistently mark the fixed long syllables on the first and fourth syllables via a combination of raised and multiple pitches. As a guide to this wider tradition, only the notation with the clearest implications for pitch height is transcribed below (i.e from Paris BNdF lat. 7183) with clarification of the basic pitch content of the neumes added in stemless noteheads immediately below. The regularity of association between the fixed long syllables and higher picthes in the northern French notation suggests an informing recitational model, perhaps again the minor third principle as outlined in discussion of Quisquis composito (I:4). A similar principle appears to be at work in the interlinear notation in the Cambridge leaf since not only higher pitches but also melodic figures of more than one pitch are routinely placed on the fixed long syllables in the line, i.e. at the first and fourth syllables. The simplest interpretation of the surviving set of notations is that the interlinear melody in the Cambridge leaf represents an elaborated version of the minor-third recitation principle that informs the rest of the notated tradition. Proceeding from this basis, a melodic reconstruction may be attempted.
The version of the reconstructed melody given here was prepared in conjunction with Benjamin Bagby and Hanna Marti, informed by experimentation with the principles outlined above. Extension of the opening six-line melody across the thirty-one line metrum was guided by repetition and excision of melodic lines within the opening unit in order to begin new strophes at significant points of textual articulation, namely lines 14, 20 and 25. For the wider notated tradition of Nubibus atris, see Barrett, The Melodic Tradition, vol. II, pp. 204-9.
