[In English, for Fabio & Claudia.]. I feel compelled somehow to mention one or two things about playing compisitons w/in this master-structure "Treatise": Because of the change of the nature of mistake then. We'll all play various written pieces during those 12 hours, on & off, & it isn't the point to perform them the way such a composition is performed still nowadays, as if the very foundations of music weren't different from, say, the cursed classical times. But they are. Whilst playing a solo piece, e.g., it's possible at any given point to leave the course of the score, play something w/ the others, then hop back into the piece at hand, repeat a line, alter it in any way etc pp. The others will accompany prima vista ("audita"?...), or contrast, object, just listen, whatever comes to their mind. So, the nature of what it means "to play it wrong" itself changes: Any sound can become music, & thus a mistake is no longe such but a deviation which in turn can/may become another strain of evoluting the composition left behind to something completely else. So, in effect, the compositions we bring into these 12 hours aren't to be immaculately rehearsed as if we're to play some M*BEEEEP!*t or by this other composer-person we don't mention by name any more, the scores should be practised enough so they stay themselves at least temporarily, but we have to be flexible & relentlessly attentive enough to cut through it at any time it may be required form us. Even when this means to commit a mistake. (I made a heap of those compositions I'll bring in, one for each instrument, & am practising a piece of it or two each day; so I won't be surprised -these are my absolute favorite pieces anyway, so I'm playing them on & on in any case- but whenever I'm stumbling so to say I think about it as a chance to do something else. Exactly as Cage said all art is about, to do something else.