Hi Marjin,I don't get the part about the concerto and the trio, but I get the part about the sonata and the symphony.Ummmm..... I am not a music researcher, but I think it is possible that he liked the same theme and used it over again. So I am kind of leaned towards the "consciously done" side, I guess.For everyone to take a look at, I have attached the photos of the parts he is mentioning. The link for the trio is here:https://www.imslp.org/wiki/Piano_Trio_in_G_major,_Op.1_No.2_(Beethoven,_Ludwig_van)Sonata is by the Schenker Edition, reprinted by Dover Publications. (S4-001)Symphony is by Dover Publications. (S4-002)Concerto is by Ernst Eulenburg Publications. (S4-003)Best,Natsu
I noticed the similarity between the symphony and the sonata too. This is really cool, and I'm pretty sure he did this on puropse. I guess he liked the theme and liked the idea of having a "private joke" with his listeners.I used to look for these sorts of things all the time - Beethoven really likes doing this. I actually made a list of places where this happens a few years ago but I can't find it and can't seem to remember what pieces were in it.Anyway, a lot of other composers do these sorts of things too, sometimes in a more obvious way and sometimes more subtly. It's annoying because I can't bring any examples to mind right now, but I remember I used to find a lot of leitmotif repetitions in Chopin's different works.