In the palace of Rubyland there was a ruby thief.
No one knew who he was, and the thief had everyone so fooled that the only thing known about him was that he lived in the palace, and that when you were in the palace you should always hide your jewels.
The King decided to find out who it was and he asked for help from a wise dwarf who was famed for his intelligence. The dwarf spent some days there, watching and listening, until there was another theft. The following morning the wise dwarf made all the palace inhabitants meet up together in the same room.
After inspecting them for the whole morning, and during lunch, without saying a word, the dwarf started asking them all, one by one, what they knew about the stolen jewels.
Once again, it seemed that no one had been the thief. But then, suddenly, one of the gardeners began coughing, writhing and moaning, and finally he fell to the floor.
The dwarf, with a cheeky smile, explained that the food they had just eaten was poisoned, and the only antidote for this poison was hidden inside the ruby that had been stolen the previous night.
And he explained how, some days earlier, he himself had swapped some false rubies for the genuine ones, and that he expected that only the thief would be able to save his life, since the poison was particularly quick working…
The cough and groans spread around the room and terror took hold of all present. All except one person…
A footman [servant] didn’t take long to run over to where he had hidden the jewels, from where he took the final ruby. Fortunately he would be able to open it and drink the strange liquid inside, thus saving his life. Or so he believed, because the gardener was in fact, one of the dwarf’s assistants and the poison was nothing more than a potion prepared by the little investigator to cause a few strong pains for a short while, but nothing more than that. And the footman, now found out, was arrested by the guards and taken immediately to the court.
The King, generously rewarded his wise adviser, and when he asked the dwarf what his secret was the dwarf smiled and said: I only try to get the person knowing the truth to reveal that truth.
"And who knew it? If the thief had deceived everyone…", said the king
No, your majesty, not everyone. Anyone can deceive everyone, but no one can deceive themselves.