A Christmas Puzzle
I'm too sick to blog. In the meantime, here is a puzzle I've made up for the second edition of Ansgar Beckermann's Einführung in die Logik. In fact, it's two puzzles.
Once upon a time an old and reticent king made the following announcement: "One day somebody will find a deductively sound argument proving that I haven't always said the truth. To this person I will bequeath my kindom." It was the court jester who first presented such an argument. How did the argument go?
Soon afterwards, the king died, and it came to be known that the above announcement was in fact the only sentences the king had spoken in his entire life. Thereafter, the court jester was refused the kingdom -- for logical reasons. Why?