I'm not sure who the original composer is to give credit...but it might give you a headache to try and solve this one!



White to move and mate in two. The only "hint" for now is I will confirm it really is mate in TWO moves for White. I have not made an error in the setting up of the problem so don't use that as an excuse to skip solving this one!

And Crocodile, I'm with Phobetor on this one. I've seen too many Chess books with mistakes, typos, or puzzles where the solution just plain doesn't work. The fact that the person presenting a problem says there's a solution isn't proof that he's right. Prove it using the rules of the game, not the word of the presenter. It is possible, as you yourself already demonstrated.

--Fromper

Of course! I haven't disagreed on that....

I said:
2)If black can castle, then there is no mate in 2 in this position for white. (This can be seen by examining all the moves for white)

My parenthesis is the "proof" for that and i didn't provide a more strict proof since as you said i would have to post billions of variations.
I thought this is clear....

-----------------

Also you said:
"First you say that this must be the solution because there is a solution and all other moves aren't the solution,"

I've replied that i didn't say that. And i didn't.

You replied with the following post of mine, obviously as a proof that i actually said that. But it's absolutely a different thing.

Here is the post of me:
"1)There is a mate in 2 for white in this position. (This was given by the author)
2)If black can castle, then there is no mate in 2 in this position for white. (This can be seen by examining all the moves for white)

What's the result of 1) and 2)?
That black can't castle!"


There i'm NOT saying(super obviously) that all other moves except 1.Qa1, do NOT mate for white in 2. How in the world did you come up with this?

I never said that(because it will be a mistake):
"There is a solution AND all other moves(except Qa1) aren't the solution so Qa1 is a solution."

I just said that: "If black can castle then all moves(with Qa1) aren't the solution."

This is COMPLETELY different that the above you said i've said.....


I also said that: "Qa1 is a mate in 2, so it is a solution.
WITHOUT having to care if other solutions exist too since the problems does not ask this."

So we should not take for granted anything that the author says? We should question the legality of every statement the author says? Correct?
Yes i guess.

So i ask again:

The author of this problem gave:
1)A Chess position which is just a statement of the form: "We have a Chess position with a FEN: ././././././."
2)A statement of the form: "White can mate in 2 from this position"
3)Give the mate in 2 for white.

The first 2 are statements the author gave.
The last is the question.

You say that we should not trust his statements.
Why we should trust his 1) statement. In other words why we should trust that the diagram(chess position) he gave is correct?
I mean we should not trust his 2) statement so why we have to trust his 1) statement too?
First point.

Another point(i again already said but anyway):
When we are presented by a problem we try to solve this problem! NOT to prove the validness of this problem. That would be another problem. Different than the one we were originally faced to prove.

Still that comes down to the same thing: You didn't prove that if black can castle, all moves aren't the solution. So if you insist on proving it that way, your proof is still incorrect.

But like Fromper said: you should prove that castling is illegal using the rules of the game, not using the statement that there must be mate. You don't need that to prove there's a mate in two, so why use it to create doubt and confusion?

If you so much insist on analyzing words rather than positions, just read the problem as "White to play. Can he mate in two? If so, how?".

I will not repeat myself for Xth time....


Yet one more thing on your: "You didn't prove that if black can castle, all moves aren't the solution.So if you insist on proving it that way, your proof is still incorrect."

Do you mean i had to give ALL billion variations that prove white has not a mate in 2 if black can castle?
Do you say that in every mate in 4 for example problem, you only consider a solution that consists of all trillions of trillions of variations with every possible continuation that covers all legal 7-ply continuations for this position?

So your solution to the problem i gave(Tricky hyper-combination! topic):
"Oh maybe 1. Nde5 Bd5 2. Nc6 Bxc6 3. Nxe7 Be4 4. Nc6 Bxc6 5. e7 h2 6. e8=Q h1=Q 7. Bb7+ Bxb7 8. Kxc7 Bc8 9. Qxc8#"

....is not correct since you did not gave all possible 17 ply continuations.

Also your "Yes, your solution is right" as a reply to graw81 in the "Hard puzzle" topic, is not correct since graw81 does not give all possible 5-ply continuations for the problem.


I agree with you that such a solution would be the ideal one, but obviously we can't expect from anyone to give such a solution.
So why you expected from me to give all billions of continuations while at the same time you propose a solution that does not keep up with this rule?


As you see you are continuously fall into contradictions.
Here you propose that i have to give all(yes you've said ALL as you can see for yourself) continuations, yet in other posts you give only 1 and also said a solution that does not contained all continuations was correct.



That would be ANOTHER different problem that the one of the topic and i would solve it with the exact same way of my 2nd solution for the original problem:

Black can't castle because if we find the previous move for black then we have that:
All 3 Pawns obviously couldn't move so either the King or Rook moved, so castle is forbidden for this position for black.
So, etc.....

When I posted the problem, I did expect it to solved as a "puzzle within a puzzle" problem. I apologize for not making my expectations clear in my first post. Phobetor did PM me the answer I was seeking...

My bad that I defended it the way of "You didn't prove it enough". I should just go back to the "It doesn't prove it" point:

Here you need to prove that black can't castle. The fact that black can't castle has nothing to do with if white can mate in two or not. You can prove that black can't castle here, even if white didn't have a mate in two. So you don't need the fact that white can indeed mate in two and you mustn't use it either; you have to show that white can mate in two, and give the moves that force that mate.

And we all know that the rhetorical way is the way asked for. We all don't doubt about that theory, and that it 100% proves it. So why insist on doing it this way at all?

But like you said, this is getting repetitive.

Geesh, my head is spinning

It is mate in two puzzle. And the solution is 1.Qa1 because Black can't castle anymore.

Prove:

To prove whetter Black can castle or not, lets observe the last position of diagram.

White to move means : THE LAST MOVE before this initial position happened, must be BLACK MOVE. Ok below are the possibilities

CASE 1 (Castling rules)

If Black can castle, Ke8 and Ra8 must never leave their original position, so the last Black's move can't be King Ke8 or Rook Ra8.

CASE 2 (last Black's move is g3 pawn)

It is impossible ! Why?, Bcoz there are white pieces in f4, g4 or h4.
If Black pawn could reach g3, in the next move white must move their pieces to fill f4, g4,or h4 to get our initial position of this puzzle.

ex: assumed in 70th move

70....f4xg3 71.Bf4
70....h4xg3 71.h4

And now is Black turn. So what is the last Black's move?

CASE 3 (last Black's move is another pieces whom has been disappeared by White)

It is impossible too! Why?, Bcoz to disappear these another Black pieces from board, white must kill (hit) it to get our initial position of this puzzle.

ex: assumed in 70th move

70....Na6
71.Qxa6

And now is Black turn. So what is the last Black's move?


CONCLUSION

So the last Black's move before this initial position is SURELY King Ke8 or Rook Ra8, means Black can not castle anymore

Thanks.

Wow. Nice logic, and a lot nicer than the Croc-Fromper-Phobetor argument.