Not that most people consider it as such, but technically, A Mind Beside Itself is one composition. If it were separate songs, then there would be no need for the title "A Mind Beside Itself" nor for the 3 parts to be labeled using roman numerals. Even when MP initially was going over the setlists with me for the tourography, whenever all 3 parts were played in sequence, he never spoke of "Erotomania, Voices and The Silent Man" but rather just of "A Mind Beside Itself".
That being said, most fans would consider Erotomania, Voices and The Silent Man as 3 separate songs, which is understandable. Each part is distinctly different from the other 2; each part is tracked separately on the CD; and as far as I can remember, the band never made reference to it being a 20-minute epic in the same way as they did when ACoS was released.
In any case, I did vote for AMBI (and SDoIT). But I wouldn't be surprised if only a few people agree with me.