Virtual Opposition - For the Love of god please explain

"... c7 and f2 are black. ..." - mariners234

"... However c7 and f2 are nothing to do with this entire post lol. …" - sg4rb0

The rule is based on the idea that Black's move, 1...Kf7, so-to-speak, "builds a rectangle" determined by the position of the white king and the new position of the black king. That rectangle has the corners as indicated by peepchuy, "f7-c7-f2-c2". The rule is that one gains the opposition if one makes a move that "builds a rectangle" with all of the corners having the same color. 1...Kf7 does not gain the opposition because f7, c7, f2, and c2 are not all the same color.

I do not feel up to the task of indicating "decision offshoots", but I think that perhaps one line is sufficient to indicate the idea.

Here is a good example of white using the distant opposition (which he doesn't posess!) to break through.

Hi pfren.  That puzzle, I'm even more confused now.  Since the correct move is Kg6.  I just don't understand how that obtains opposition, because the black king can play Ka6, and there is 5 squares between kings which means surely black has the opposition?  Whenever I play these kinds of opposition excersizes, I never get them right (except when the kings are in the same file).  It's so infuriating for me, because from that puzzle, I don't see how you can know what to play without working out all the possibilities for where the can king move on each turn.  Is there a system you are using in your mind to know quickly what to play, or do you just spend like 10-15minutes working out all of the possibilities?

How do you know that the correct move is 1.Kg6?

If you used an engine to find out, then- congratulations! You have managed to avoid learning something...

White can NOT gain the opposition in that position, which belongs to Black (1 rank and 5 files distance from the initial position with white to move). But he can use the threat to win the opposition, to drive Black's king at the mined square a8:

1.Kg6! Ka6 2.Kg7! Ka7 (Black has to keep the distant opposition, else the loss is trivial) 3.Kg8! Ka8 (3...Ka6 loses because after 4.Kf8 Kb6 5.Ke8 Kc6 6.Kd8 Black cannot use the d6 square) 4.c5! and white wins (the e5 pawn is promoted with check).

Notice that trying to do the same with 1.Kf6? does not work because of 1...Kb6 2.Kf7 (too late for 2.Kg7 because of 2...Kc7) Kb7 3.Kf8 Kb8 4.c5 Kc7! and Black is OK.

In itself, the concept of distant opposition, is, I think, not hard and possible to see at a glance. The difficulty, I think, is in discerning how the pawns determine when the distant opposition is useful and seeing how to maneuver in order to maintain a winning opportunity. That can be quite hard, and I suspect that, for me, more than fifteen minutes could have gone by without a perception of a solution to IM pfren’s problem. I don’t think that one should be ashamed if one encounters a problem where one does not quickly know what to do.

Oh i see now pfren.  So we don't gain the opposition, but we drive the king back with the threat of (if he doesn't follow up the board to a8) to come in and steal opposition and his pawn.  Then we donate a pawn and win the game (without any need for the opposition).  I was just really confused because I was trying to find a way to win the opposition and I couldn't.  Thanks for that pfren!

In itself, the concept of distant opposition, is, I think, not hard and possible to see at a glance. The difficulty, I think, is in discerning how the pawns determine when the distant opposition is useful and seeing how to maneuver in order to maintain a winning opportunity.

That's why u probably hafta add the pawn(s) to make it go from virtual to practical. I got Kg6 correct 'cuz I thought correct was to triangulate (wrong concept). But I never wooda got Kg7 (let alone Kg8...setting up the promoting check).

I agree that adding pawns is desirable when one wants a practical example, but I nevertheless think that it is sometimes helpful to first consider an explanation of distant opposition for a position with just two kings.

....ohh heavens.

@ kindaspongey: Yes, that's the puzzle I was referring to. In your pgn white has the advantage and 'wins'  the game.

yup, that's a good explanation! thanks

Given that the square colours alternate along both ranks and files your criterion would appear to be identical with the corners of the rectangle being the same colour.

Edit: Except it should say between or including, because kings on the same or adjacent rows (ranks or files) would normally both be regarded as having zero (an even number) rows of the same kind between.

There is nothing wrong with using the edge colours along a rank and file of the rectangle with kings as corners to determine the corresponding parities, indeed many mathematicians would prefer it. (There are three kinds of mathematician.)