THE CARD PARADOX
Imagine you’re holding a postcard in your hand, on one side of which is written, “The statement on the other side of this card is true.” We’ll call that Statement A. Turn the card over, and the opposite side reads, “The statement on the other side of this card is false” (Statement B). Trying to assign any truth to either Statement A or B, however, leads to a paradox: if A is true then B must be as well, but for B to be true, A has to be false. Oppositely, if A is false then B must be false too, which must ultimately make A true.
Invented by the British logician Philip Jourdain in the early 1900s, the Card Paradox is a simple variation of what is known as a “liar paradox,” in which assigning truth values to statements that purport to be either true or false produces a contradiction. An even more complicated variation of a liar paradox is the next entry on our list.
Your Answer
More puzzles to try-
How is this possible?
The day before yesterday, Chris was 7 years old. Next year, she’ll turn 10. How is this possible?Read More »Unique English Word
Which English word retains the same pronunciation, even after you take away four of its five letters?Read More »I stumble, I fly, I am there should you die riddle
I stumble, I fly, I am there should you die. I am all three as one, and I am naught ...Read More »Stamp buying riddle
Yesterday John’s mother asked him to buy some stamps. Stamps, in the land of Puzzlefry, are available in 3p, 9p, ...Read More »End of everything
What is the end of everything?Read More »We clap for it
It is an object, everywhere it goes people clap for it. What is it?Read More »Best Man Always wear me
A finger goes in me. You fiddle with me when you’re bored. The best man always has me first. What ...Read More »What is the chance of flipping heads again?
You have three coins. One always comes up heads, one always comes up tails, and one is just a regular ...Read More »English Letters
Name an English word of more than two letters that both begins and ends with the letters “he” in the ...Read More »Life Line
It is as light as a feather, yet the strongest of men cannot hold it for more than a minute. ...Read More »Broken Bone fixing riddle
Bone is cracked, Help Tom to Fix the Bone. Out of 14 pieces, Which is the broken part of the ...Read More »Find the Key
With the help clues provided in below image, can you find the 5 digit key?Read More »Can you find the mistake Puzzle
Can you find the mistake in the below statement?Read More »Open Poker riddle
On the game of Poker, two people play as follows: Player 1 takes any 5 cards of his choice from ...Read More »Triangular Puzzle
Can you find a relation between the given figures? And find the missing number?Read More »You can Win or Loose
You can win me and lose me but never buy me You can not eat me and never want to ...Read More »Interview with fun riddle
During an interview in a renowned company, while answering the question, the candidate became quite nervous. The interviewer was generous ...Read More »Which is day yesterday
Which day would yesterday be if Thursday was four days before the day after tomorrow?Read More »Practising without getting tired
A man goes down to the beach and starts walking on the beach, he has to get to the circus ...Read More »The Arm of the Postal Service
The Arm of the Postal Service One day a man received a parcel in the post. Carefully packed inside was ...Read More »
