The chord is in measure 2 of the piece, and contains these notes: D, C#, E, G, Bb, C#, E.
A diminished 7th in Dm should have D, F, Ab, Bb, shouldn't it? This is a diminished 7th C#, so what's the D doing there?
Anyway, my impression is that diminished 7ths are much more common in organ music than in piano music. I think of them as "that organ-music chord". And if you look up diminished 7th in the same music database that komponisto linked to above, you'll see it has a much higher fraction of baroque entries than any of the other items on that list.
Perhaps part of the issue is when I hear "baroque" I think Bach, and when I hear "classical" I think Mozart. I think Bach does more weird chords than Mozart does. Or consider Beethoven's Moonlight Sonata--it's chock full of different chords juxtaposed in unusual ways, but they're almost all common chords.
Anyway, my impression is that diminished 7ths are much more common in organ music than in piano music.
I don't share this impression at all. How much piano music do you know? There's probably a lot more of it than there is of organ music. This is certainly the case in the nineteenth century, which was probably the heyday of the diminished seventh (while being the low point of the organ repertory).
...And if you look up diminished 7th in the same music database that komponisto linked to above, you'll see it has a much higher fraction of baroque entries tha
We recently established a successful Useful Concepts Repository. It got me thinking about all the useless or actively harmful concepts I had carried around for in some cases most of my life before seeing them for what they were. Then it occurred to me that I probably still have some poisonous concepts lurking in my mind, and I thought creating this thread might be one way to discover what they are.
I'll start us off with one simple example: The Bohr model of the atom as it is taught in school is a dangerous thing to keep in your head for too long. I graduated from high school believing that it was basically a correct physical representation of atoms. (And I went to a *good* high school.) Some may say that the Bohr model serves a useful role as a lie-to-children to bridge understanding to the true physics, but if so, why do so many adults still think atoms look like concentric circular orbits of electrons around a nucleus?
There's one hallmark of truly bad concepts: they actively work against correct induction. Thinking in terms of the Bohr model actively prevents you from understanding molecular bonding and, really, everything about how an atom can serve as a functional piece of a real thing like a protein or a diamond.
Bad concepts don't have to be scientific. Religion is held to be a pretty harmful concept around here. There are certain political theories which might qualify, except I expect that one man's harmful political concept is another man's core value system, so as usual we should probably stay away from politics. But I welcome input as fuzzy as common folk advice you receive that turned out to be really costly.