It's a 'discovered attack', so obviously Nd4 moves somewhere. Nf5 looks like a good start, protecting my Be3 and attacking Bg7 and Qb6 (the discovery). So, 1. Nf5 Queen moves, 2. Nxg7+ is a piece. Easy. Hmmm... Nxg7+ Kf8, better get the Knight out... but all his escape squares are covered, Black gets the piece back. And where did the Queen go when she moved? Oh, Nf5 Qxb2 attacking my Nc3. Nf5 has holes in it, let's look for something more clear-cut.
So... Nb3 covers the b2 pawn... but then just Qxe3. Ndb5, same.
Ne6 maybe? Threatens the fork so Qxe3 2. Nxc7+ Kd8 3. Nxa8 gets the exchange... but something like Qxf4 immediately, and the Knight's got Bukley's chance of getting out of the corner surely? nope, can't see a way, don't like that.
Ok, something else... save the discovery and play something else first... 1. Nd5 hit the Queen with the other Knight, looking at 2. Nc7+. Just Qd8 might not be best, but it defends the threat and then where's this 'discovered attack'?
Back to the Nf5 idea then...
And so young Sim ran in circles until conceding defeat and looked up the solution (translated from English to algebraic notation):
"White's discovered attack wins the Queen or forces checkmate: 1. Ne6! Qxe3 2. Nd5! Qe4 3. Ndc7#" - Fred Reinfeld.
Brilliant! 1. Ne6 immobilises the King, then we just put the other one on c7 by hitting the Queen again via d5, GAME OVER! There was a fault in my thought process in that I didn't notice the King's immobilisation by Ne6, and I didn't combine the Ne6 and Nd5 ideas.
Wait a minute! Did I say vague, Fred? You didn't give the solution to 1. Ne6 Qxb2. That must so obviously win the Queen that the line doesn't rate a mention, right? Let's check. 1. Ne6 Qxb2 now both my Knights are en prise... where's the killer? 2.Bd4 re-setting the discovery? 2. ... fxe6 3. Nb5 Qb4+... maybe I get the exchange at the expense of trapping my Knight in the corner again, whatever Black seems to be punching harder than I am. Where's this Queen win?
I'm sure I'll have more to say about using computer Chess engines in the future, but for now suffice to say that if this is a simple "wins the queen" for a human, Crafty will find it in no time, right?
From the diagram, Crafty whips off a search of a million positions in a few seconds.
Evaluation +0.90, depth 8 ply (4 moves)
1. Nf5 Qxb2 2. Nxg7+ Kf8 3. Nd5 Kxg7 4. exd6 Qa3 5. Nc7 Qxe3 6. Nxa8 exd6 7. Qxd6
Not awe inspiring, no Queen win in sight, but Crafty is a 'quick and dumb' engine, it's being thorough. Give it a minute at least...
Evaluation +0.99, depth 9 ply, 5.171MN (about 5 million positions searched)
1. O-O dxe5 2. Nf5 Qxb2 3. Nxg7+ Kf8 4. Ne6+ fxe6 5. Ne4 exf4 6. Bxf4
Erm, yes, +1 is certainly winnable, but this is the solution to a problem combo? Time to get ready for work, and 15 minutes later Crafty reports
Evaluation +2.03, depth 12 ply (6 moves), 55.657 million positions searched
1. Nf5 Qxb2 2. Nxg7+ Kf8 3. Nb5 Kxg7 4. Bd2 Nd4 5. Bc3
Let's leave Crafty running while we're away and ponder an old Chess story which no one seems to know, but everyone seems to know the ending of. By back analysis, we can determine the player of the white pieces to be the King, and the player of black to be his daughter's suitor. The King applies a tactic which befits a man of his status.
"You may marry the Princess my son, provided you swear an oath never to take the Queen Knight's Pawn with your Queen!".
But our man Fred was right all along as we return to discover that after about 6 hours Crafty found
Evaluation +2.61, 11.912GN, 16 ply
1. Ne6 Qxb2 2. Nxg7+ Kf8 3. Nb5 Kxg7 4. Bd2 a6 5. Bc3 Qxa1 6. Qxa1 axb5 7. exd6+ f6 8. dxe7 b4 9. Bd2 Nxe7 10. Bxb4
Yes, that's nearly 12 thousand million positions searched, and if the Prince takes the Queen Knight Pawn, there is a... erm... 'simple' win of the queen. But it's Fred who marries the princess after all. 13 hours and the Queen Knights Pawn didn't tempt him once...
Evaluation +2.28, 24.232GN, depth 17 ply
1. Ne6 Qxe3 2. Nd5 fxe6 3. Nxe3 dxe5 4. fxe5 Ndxe5 5. Bb5 Bd7 6. Qd2 O-O-O 7. O-O-O Kb8 8. Bxc6 Nxc6
Position after 8. ... Nxc6
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