The lady or the tiger

There is mathematical logical puzzle in the book "The lady or the tiger " by Raymond Smullyan. It is about a king and 12 prisoners. The King wants to get rid of them without executing them but he wants only the smart ones to survive. Therefore every prisoner face a logical puzzle he has to solve before he may enjoy freedom.

I discovered this puzzle while I surfed the internet and visited a forum. I was ethuastic and excited and could solve all puzzles by analyzing scenarios and using truth tables for notes (see wikipedia for more information on truth tables).