The redheads and the chess pieces.

The redheads and the chess pieces.

Author’s note: This is an old puzzle. I am only resurrecting it because the amazing Hannah Fry has tweeted a request for a chess-player, and I am not going to see my maths phd and decades of chess-playing go to waste simply because of a 140-character word limit and my inability to be epigrammatic. If it turns out to be an April Fools’, I shall be most disappointed.

Author’s side-note: Apologies to you dear readers, and to Kevin and Isabella, for my prolonged absence, which I may well resume presently.

Three young redheads*, cavorting naked in the moonlight one evening, were captured by a group of perverted chess-playing homicidal maniacs. The redheads watched in horror as the leader of the perverted chess-playing homicidal maniacs selected two knights and three pawns from his set. He ordered the other perverted chess-playing homicidal maniacs to tie the captives’ hands behind their respective backs. He then set the redheads standing in an equilateral triangle with edges of almost arbitrary length 10 metres, to prevent whispering or wiggling and gesticulative hints between the captives. He explained, as he placed one of the five chess pieces standing on each of the captives’ heads, that if any of them dropped their chess piece then they would all be killed. Further, they would each be asked what chess piece was on their heads – a simple multiple-choice question, in effect, where one correct answer would lead to instant freedom for all three. One of the redheads asked if there was to be negative marking, which reminded the leader of the perverted chess-playing homicidal maniacs that yes, in fact, an incorrect answer would lead to the redheads all being summarily executed whereupon their skins would be converted into lampshades for the table lamps which the perverted chess-playing homicidal maniacs had recently won at a table quiz**, which had ironically turned out to be about tables and left the participants feeling a little bitter – hence the capturing and threats of death and so on, which they would not under normal circumstances condone.

And so, without further ado, the first redhead was asked what chess piece was on her head. She looked at the chess pieces on the heads of her friends*** and hadn’t a fucking clue, and burst into tears because she was an emotional sort. It was a wonder that she managed to keep the chess piece balanced on her head at all. The second redhead was then asked what chess piece was on her head****. She asked what would happen if none of them answered, and after a moment’s contemplation the leader of the perverted chess-playing homicidal maniacs conceded that he hadn’t considered that eventuality, but that she could rest assured that he would conceive an equally heinous yet tedious fate for them all. So after briefly attempting to twist her head at some odd angle and rolling her eyes up into her skull in an effort to see through it to the chess piece, the second redhead conceded that she did not know what chess piece was on her head either. The final redhead had lost her glasses, which was just typical of her, and she was unfortunately yet intriguingly effectively blind without them. So while she had seen the pieces when they were selected, she could now barely distinguish the other girls’ blurry arses from their blurry elbows, nevermind which sodding chess piece was balanced on their blurry heads. In any event – she didn’t actually know what the chess-pieces were called, having never made her way to the chess club meetings whilst she was at university. Scarlet for her mother for having her, eh? But after a moment’s thought she was able to work out what the piece on her head ought to look like. She described the piece to the leader of the perverted chess-playing homicidal maniacs, who, being an honourable sort, let the other two girls go, but was so infuriated at the final redhead‘s ignorance that he clubbed her slowly to death with a copy of a small publication about mathematics, chess, and toilets.

The moral of the story is, obviously, go to chess club – Wednesdays from 8 in Smokey’s*****.
The question is: what piece was on the final redhead‘s head, and how did she know?

* These ladies’ hair colour has remained unchanged for the past four years – we do not pander.

**For the benefit of our international readers, a table quiz is what the Irish call a pub quiz. Why, I do not know. But yes, in answer to your inevitable question, we did actually host a pub quiz where all 107 of the questions were about tables. It was unforgettable.

***In truth, they were not actually friends at all, and had never even met before being thrust together as part of this sick, perverted fantasy.. eh.. puzzle..
Life’s funny, eh?

****The problem may call for some suspension of disbelief. Primarily, it must be assumed that the redheads in question are intelligent. Pretend they’re expert logicians or something like that.

*****For the benefit of our international readers: Smokey’s Cafe, National University of Ireland, Galway, Galway, Ireland.