Measures 1–3: The diminished fourth traversed by the upper voice does not represent a genuine linear progression; the opening D

is an inner voice inflected to D

when the G

-major harmony appears. The bass B

is retained through this inflection of the third coupled with a 5–6 exchange. Typically, this would represent a single prolonged harmony, but here the impression of E

minor is initially so strong that it seems warranted to assign the first harmony its own
Stufe.