The analysis of the aria “Lascia ch'io pianga” by Haendel according to the thorough bass method, shows us how the composer refer in this piece to the typical compositional procedures of baroque music. The aria starts with a pedal (frame, according to Joel Lester's terminology) followed by a cadence harmonized according the regle de l'octave both in ascending and descending motion (MM. 5-8). The second episode starting at M. 8 consists of a sequence, precisely a modified sequence, in which the subsequent is slightly modified at the end introducing a new harmony on the second beat of M. 12 that leads to a final cadence with a modulation to the original key. The regle is always working also in the sequence, it is just applied…show more content… In “Lascia ch'io pianga” is possible to understand all the harmonies as fifths and sevenths but the bass-line motion not always moves naturally by fifths and fourths. In many cases, through the use of the double-emploi, is has been possible to correct some irregular motions into fifth motion, but still for some of them it hasn’t been possible. Probably the most evident example is the motion by second occurring between MM. 6 and 7, and between MM. 11 and 12. The fundamental-bass analysis bring into play notes that are supposed, that are not in the score but affect the music as the roots of a tree feed the last leaf on the highest branch. In this case, we can see how the sense of motion that we perceive listening to this aria is perfectly explained and justified by the succession of seventh chord and fifth chord, as the epitome of the arsi-tesi feeling in music.
Even in the first two measures, that look really simple in the thorough bass analysis, we can still discover something that makes this beginning not so obvious. In the first measure the F is transformed into D with a seventh chord on top, and the accumulation of this seventh with the next one in the second measure create a sense of instability and a need to resolve. In the next measures this tension will be released through a succession of 5-chord with two final combinations 7-5 to close the