Positional Superko / Example

Just before the start position, White to move  

is just showing White's last move. This sets the stage for the position to be repeated (or rather banned from repetition).

Black cannot play the marked point in positional superko.  

If black plays at the marked point, it creates a position identical to the one after in the first diagram. For positional superko it doesn't matter that Black is making the move instead of White.
yoyoma - I reorganized the diagrams to make a easier to see which two positions would be identical if the illegal move was played. The following remarks were originally about the old diagrams:

willemien - Notice the stone that is missing in the starting position. So the positions are not the same.

(if white 2 was a pass then it would be a situational superko the same player is to move at both positions)

Herman: The position that is being repeated is the one after . So capturing after is legal under situational superko, but illegal under positional superko. Hence the page name :)