We sat motionless opposite each other. I was suspicious of the man opposite me, but bowed, as protocol required. And then, with lightning quickness, I loosened my sword from its scabbard and in one swift movement cut down my enemy. The blow delivered, I focused my entire attention on the lifeless form slumped before me, flicking the blood off the blade and replacing my sword in its scabbard.

I'm not a murderer, nor a samurai. I'm a practitioner of the martial art of iaido, the exercise of perfect swordsmanship -- using a real sword -- against an imaginary opponent or opponents. When practicing a waza (set form), the opponent is visualized so powerfully as to seem almost real. Anything less may lead to a lapse in concentration, and in sword fighting, one gap in your defense and you're as good as dead.

"A katana is a highly efficient killing tool, just like a spear or a bow," says Esaka Seigen, an iaido master with more than 47 years' experience, who holds the highest rank of hanshi, 10th dan. "But it is more than just a weapon; it is a means of training the heart and mind so that it takes you beyond cutting to trying to achieve wa, or harmony with others. This is what I am trying to achieve through iaido."