2nds: Melodic 2nds lead and Harmonic 2nds Dilute
ahhh 2nds the most indefinite harmonic interval that any scale or modality has ever known. Now we love 2nds as passing tones because they lead into the big "moment" that happens; this is good, we need foils to let us do what we want and move as we wish. As it stands though 2nds have highly outdated their peak of actual necessity, it was in the classical era with mozart and haydn. They used them to lead into the phrase not to dilute the phrase; take mozart piano sonata 16, most of what that sonata is, is stepwise motion to the big beats of 1 and 3. Now I believe mozart did this because he knew how notes functioned and where/what was the thing he was driving towards. A thing to note is that they are done melodically instead of harmonically; melodic 2nds lead and harmonic 2nds dilute. Which is why they are not considered functional harmony because when you get note close together is scrambles where the "root" is. In modal arabic music the 2nds are used because they lead to the strong tendency tones of the mode so you get the augmented 2nds and the neutral 2nds to divide the larger scale into small parts that is then used to ornament and "toy" with. Now all this is good but what im actually getting at is that 2nds don't define any thing they only lead and resolve (two in the same), and the glory of them is that they prolong lines to the extent of your imagination. Now I want to dissect the idea of the augmented 2nd; its an interesting idea because it still functions as a 2nd but as a minor 3rd as well, so a big leap is made "going from flat two to three" that the flat two plays with 1 and three plays with 4 which in arabic modality based off of d. So that moving from 1 to 4 is clarified very specifically; four is a big deal so seconds just play off of what they want to, to move from 1 to 4. The world gets intensified in what it wants too at that moment through all of its amalgamations of the conscious spirit seeing its self. which is why the 2nds get moved into and out of the spotlight
