Legal position?

Legal position?

Posers and Puzzles

Cookies help us deliver our Services. By using our Services or clicking I agree, you agree to our use of cookies. Learn More.

h

Joined
25 Apr 06
Moves
5939
13 May 08

Black

White

S
Caninus Interruptus

2014.05.01

Joined
11 Apr 07
Moves
92274
13 May 08
1 edit

Originally posted by heinzkat
Black
[fen]8/8/3KPk2/8/8/8/8/B7[/fen]
White
Nope, not legal. [I suspect the diagram did not come out as intended.]

h

Joined
25 Apr 06
Moves
5939
13 May 08

Originally posted by SwissGambit
Nope.
SOLV'D (SwissGambit)

h

Joined
25 Apr 06
Moves
5939
13 May 08

Pointe of the PM by Jirakon
Nope, not legal.
SOLV'D (Jirakon). The answer is very complicated, as you can see...

Quiz Master

RHP Arms

Joined
09 Jun 07
Moves
48793
13 May 08

Originally posted by SwissGambit
Nope, not legal. [I suspect the diagram did not come out as intended.]
The board is upside down and white has just promoted a pawn to a bishop. ... else its illegal.

h

Joined
25 Apr 06
Moves
5939
13 May 08

Originally posted by wolfgang59
illegal.
SOLV'D (wolfgang59)

Quiz Master

RHP Arms

Joined
09 Jun 07
Moves
48793
13 May 08

Sorry I should have PMed you but didnt think I was right.
(I NEVER SOLVE CHESS PROBLEMS!) LOL

h

Joined
25 Apr 06
Moves
5939
13 May 08

b) wK->d7. Why is this position not illegal anymore?

c

Joined
27 Apr 08
Moves
473
13 May 08

Originally posted by heinzkat
b) wK->d7. Why is this position not illegal anymore?
I can't see a reason... maybe I'm just not good at this. Did you mean wKd5?

D

Joined
25 Aug 06
Moves
0
13 May 08

Originally posted by heinzkat
b) wK->d7. Why is this position not illegal anymore?
e. p.

c

Joined
27 Apr 08
Moves
473
13 May 08

Originally posted by David113
e. p.
Good one! Didn't consider that.

h

Joined
25 Apr 06
Moves
5939
13 May 08

Originally posted by David113
e. p.
Then why was e.p. not possible in the 'a)' part of the problem?

c

Joined
27 Apr 08
Moves
473
13 May 08
1 edit

Originally posted by heinzkat
Then why was e.p. not possible in the 'a)' part of the problem?
bPe7 would put wKd6 in check (i.e. both kings would be in check simultaneously, bK from wBa1).

h

Joined
25 Apr 06
Moves
5939
13 May 08

Originally posted by curseknight
bPe7 would put wKd6 in check.
Yes... therefore the previous moves cannot have been d4-d5+, e7-e5, d5xe6 e.p.+, since White cannot have played d4-d5 while his own King was in check. Therefore, the first position is illegal.

With the wK->d7 the previous moves can/must have been (in order to reach the position) d4-d5+, e7-e5. d4xe6 e.p.+.

I welcome better thought out explanations.

(on a sidenote, 'can have been', is there a better construction to say this?)

c

Joined
27 Apr 08
Moves
473
13 May 08
1 edit

Originally posted by heinzkat
Yes... therefore the previous moves cannot have been d4-d5+, e7-e5, d5xe6 e.p.+, since White cannot have played d4-d5 while his own King was in check. Therefore, the first position is illegal.

With the wK->d7 the previous moves can/must have been (in order to reach the position) d4-d5+, e7-e5. d4xe6 e.p.+.

I welcome better thought out explanations.

(on a sidenote, 'can have been', is there a better construction to say this?)
"were possibly" might be useful there. Good problem, at first I could not see how en passant was possible, forgetting the pawn check.