Letter: A new paradox?

Sir: Gilbert Adair's paradox ("When pure logic is plain absurd", 5 September) is similar to "The Unexpected Hanging".

A man is sentenced to be hanged within the next seven days, but is told by the judge that the day of his execution will come as a surprise. He reasons that he cannot be hanged on the seventh day, because if he lives through the first six days then he will not be surprised to die on the seventh.

Having ruled out the last day, the logical slide begins and he rules out execution on the sixth day by the same reasoning. He can then work through the entire week and comes to the conclusion that he cannot be hanged during that week and be surprised as the judge had said.

He is executed on the seventh day and he is, of course, surprised.