The Blue-Faced Men of Logic: A Chess Grandmaster's Puzzle for the Mind

Delve into a mind-bending logic puzzle from Jonathan Rowson's "The Moves that Matter," exploring the surprising connections between chess, philosophy, and critical thinking.

In the book "The Moves that Matter: A Chess Grandmaster on the Game of Life," Jonathan Rowson attempts to describe his own concentration process in a game of chess and presents the following puzzle:

This challenge is revealed by a logic puzzle that I love, which I learned from the philosopher of mind John Hawthorne. The puzzle concerns three men on an island who all have blue faces. It is wonderfully convoluted, so please suspend disbelief, forget common sense, and search for the Sherlock Holmes inside.

The situation on the island is a little delicate. The three blue-faced men see each other every day, but none of them can see his own face. They all know that their face is either red or blue, but if any of them discovers the colour of their own face they have to shoot themselves at the next stroke of midnight exactly. Those are the rules. A little twisted, I know, but clear enough to live by.

Careless talk costs lives, so they don’t speak to each other, and never dare to see their own reflection. Yet despite the pressure and ambient tension, they live together in blissful ignorance for several years. Then one day a Scottish tourist called Jim arrives on the island, all the way from Glasgow. Jim chose this island because he was trying to shake off an incipient midlife crisis and couldn’t face the tedium of another beach holiday in Spain.

However, Jim is an accountant, not an anthropologist. After a few perplexing days with the natives he could not handle the tension and felt an uncontrollable urge to make a West of Scotland wisecrack. To his credit, Jim was careful to tell them something he assumed they must already know, and after getting on his boat he said ‘At least one of you has a blue face, eh!’ And off he went from the island, back to Glasgow.

Not that night, not the following night, but on the third midnight, all three men shot themselves. The first question is: Why? The second question is: What was the new information that Jim told them that they didn’t already know? Many intuit the answer to the first question long before being able to articulate the answer to the second.

Here lies the challenge to solve the puzzle - if you are curious to know the answer, please buy the book. Jonathan Rowson explains the solution in detail. Beyond this, it's truly interesting how the author exposes his thought process and dissects it in detail for us all to appreciate.

Thank you for your time. Leave your thoughts in the comments. Enjoy the day!