[Smt-talk] Passing and Neighboring 6/4s

[S. Alexander Reed]

As Dr. Tymoczko is certainly aware (as shown in his "Root Motion, 
Function, Scale Degree" paper), various texts treat harmonic 
motion with different rubrics, some of which account more 
completely and/or precisely for the actual harmonic language of 
the common practice period.  I'm thinking back to how I learned 
second inversion treatments as an undergraduate (using first the 
Piston text, then the Kostka/Payne); the neighbor 6/4 never really 
entered the conversation.  As I look now at my copy of 
Kostka/Payne, the authors allow for four uses of the 6/4:

1. via a bass arpeggiation/bass melody (which is, for my money, 
not so much a question of chordal harmony as it is a contrapuntal 
one)

2. as part of a I6/4->V cadence

3. via a passing 6/4

4. as a pedal tone (e.g. I->IV6/4->I).

Dr. Tymoczko cites the IV6->I6/4->ii6 as an example of a common 
passing 6/4; indeed, it shows up in measure 25 of K.309, mvmt. 3.  
I wonder though whether this "works" because the progression of IV 
to ii is idiomatic even without the I6/4 in between.  The same 
could be said about the pedal 6/4 chords mentioned in the original 
post (e.g. it is of course unproblematic for I to go to I; for 
thoughts on ii->V6/4->ii, consider N. Cook's discussion of chord 
succession versus progression), or for the classic voice exchange 
I->V6/4->I6.  What all of these suggest is that the 6/4 chord, 
whatever it may be, is itself treated as a collection of 
non-harmonic tones between two otherwise acceptable chords in a 
progression.  If students are taught that rule, then non-idiomatic 
but otherwise "technically" acceptable progressions like 
V4/2->vi6/4->ii are no longer possible, and as a result we have a 
more "correct" theory of harmony.

So the next question would be: can anyone find any actual examples 
of a 6/4 chord bridging the gap between two chords that, according 
to the conventions of harmonic progression (see Tymoczko's 
aforementioned paper), do not follow one another?

S. Alexander Reed
Assistant Professor
University of Florida

alexreed at ufl.edu

PS: I am nagged by the thought that I->iii6/4->vi is as uncommon 
as the original post seems to suggest; am I crazy for believing it 
to be part of the classical language?