Beethoven as Philosopher

The title is completely misleading, I'll tell you right off! Instead this is going to be a bit of forensic musicology. One of my favorite books, and one I hope to finish reading one day, is by Frederick Copleston, S. J., his A History of Philosophy in nine hefty volumes. It was originally published in the 60s and I started reading it in the 70s, but hit a wall in volume vi when we got to Kant. But I've been getting back to it in a newish edition. I was just reading the chapter on Marx in volume vii when I noticed something odd about the cover:

Do you see it? No? Ok, here is the cover to volume ix for comparison:

Everything is just as it should be. The volume covers philosophy from the French Revolution, represented by a distorted detail from the famous painting by Eugène Delacroix, "La liberté guidant le peuple":

Click to enlarge

And there is a photo of Jean-Paul Sartre (though not one I can find the original of--I suspect they added the dark glasses!):

Ok, now go look at the first cover again. See what's odd? There is an image of a half-mask such as might appear in a Venetian masque, and that guy with the pen and manuscript. Which philosopher is he? Kierkegaard, maybe? Nope, that is a very famous portrait of Beethoven by Joseph Karl Stieler from 1820:

Absolutely no doubt about it! They got the wrong guy! Beethoven may be many things, but he is emphatically not a post-Kantian idealist!