Mind Games goes on the road to bring you an ancient brainteaser, and some tantalising F-words.
20. The fork in the road
You’re travelling on a road through a strange country, heading for Eldorado, when the road splits in two. The fork is guarded by identical twin brothers. You’ve heard about these guys: you know that one brother always tells the truth and the other brother always lies. But you can’t tell which is which.
How can you find out, by asking just one question, which road leads to Eldorado?
Thanks to reader William Binedell for suggesting this classic brainteaser!
21. The F-words
Count how many times the letter F appears in the sentence below – read it just once, quickly.
FINISHED FILES ARE THE
RESULT OF YEARS OF SCIENTIFIC
STUDY COMBINED WITH THE
EXPERIENCE OF YEARS.
How many Fs did you find? See answer.
- Compiled by Olivia Rose-Innes and Senora Sine Thirteen, Health24, July 2011
Translation of Philetas’ epitaph is by Stock, 1908, quoted in B. Mates, Stoic Logic,1961.
J. Barwise & J. Etchemendy, The Liar, 1987.
R. Smullyan, What is the name of this book?, 1978
R. Sutz & P. Weverka, Speed Reading For Dummies
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