Actually, mine's number 8. It's a kind of antithesis to 5, the most personal and least "formal" of all his symphonies. Instead of the fierce irony of 5 (I'll say imo to prevent a fight, but I'm pretty sure about this), we are let into a completely unique sound-world where the orchestra is divided into blocks modulate amongst themselves for minutes at a time. Instead of the horrifying D major chords at the end of 5, we are given a sort of catharsis, a profound inward peace. 5 seems to defeat itself, imo, because if the world really is an insurmountable as that symphony argues, what is the point of writing symphonies at all? That said, it's still a pretty amazing piece. All the rest, too.