In feudal Japan bushido ("the way of the warrior") was the code of moral principles which the samurai were required or instructed to observe. It is a code unuttered and unwritten; an organic growth of decades and centuries of military career. In order to become a samurai this code had to be mastered.

The tsuba is the guard at the end of the grip of bladed Japanese weapons such as the katana. It contributes to the balance of the weapon, but more importantly it prevents the hand from sliding onto the blade.

A human invested with the power to command and the power to kill was expected to demonstrate equally extraordinary powers of benevolence and mercy: Love, magnanimity, affection for others, sympathy and pity.