Here is the introduction to a Brahms intermezzo, Op. 76 No. 7 --



Now here's the challenge. I'm going to post 2 excerpts from later in this piece. They both sound very different from the introduction, but are actually very similar to it anyway. Point out at least one way that each excerpt is derived from the introduction:



and




It's actually really cool how Brahms wrote this piece. And the music is beautiful, too.

The motive from the tenor line in bars 1 and 2 of the introduction reappears in rhythmic diminution (sort of) in the soprano line of the first excerpt, and again in the soprano and tenor of the second excerpt.

Now, where do the sequences in the 2nd passage come from?

The first sequence cell of the second excerpt could be described as "up a semitone, down a third" (disregarding the repeated note.)That's a feature of the same tenor-voice motive in the intro. The second sequence cell is "iambic semitone downward" which occurs in the soprano of the first full bar.
This is getting pretty tenuous...you can't get any smaller than a two-note motive fragment.
Right you are. I wasn't familiar with this piece before. Thanks for the opportunity to get acquainted with it.

Now suppose that the opening soprano melody itself is derived from some other piece of music. I don't claim that it actually is, but just suppose. What piece would that be?

Not meaning to interrupt this lovely dialogue, but I too have wondered whether the Brahms is a conscious hommage to the other composer Ferdinand is referring to. I myself tend to think so, since Brahms (being something of a historicist) had such a massive amount of repertoire in his head (more so than many musicians of his time), and he even helped edit the works of the earlier composer.
Any Brahms thread will most likely get a response from me, but for now I'll politely exit...

One device he uses is a link. The bass line of the last full measure of the opening becomes the melody at the beginning of excerpt 1 (in 8th notes.) This trick is used elsewhere in Brahms and is discussed in the theoretical literature as "developing variation."

The rhythm at the end of the first line of the opening is found at the end of both excerpts. And within excerpt #2, the bass line of mm. 3-4 is the same as the soprano in mm. 1-2. (And the soprano of 3-4 is the bass from 1-2.)

Right -- I think it also comes from the descending scale in the soprano of mm. 4-6 of the intro -- hence the (now chromatic) bass line, and the whole idea of sequences, in the 2nd passage.