Ludwig van Beethoven Whenever one speaks about Beethoven’s piano music, it is usually his sonatas that come to mind. However, his other works for this instrument are of no less significance. Thus it is not a coincidence that Beethoven published the majority of his Bagatellen with an opus number, as this went hand in hand with a certain regard for the pieces in question: they represent Beethoven’s lighter, more accessible side, disproving his all too hastily attributed reputation as a master of the weighty and serious.