Three Samurais were arguing which of them was the best Samurai out of the three. Each believed they were the best. In the middle of their discussion, a fly comes in through the window and starts buzzing around them. Getting an idea, the first samurai takes out his sword and slashes through the air! The fly falls to ground, completely split into two equal pieces. The two other samurais were impressed.
Not to be outdone, the second samurai steps up. Another fly comes in through the window and he slashes his sword! The fly drops to the ground, still moving and very much alive, but its wings were completely sliced off. The other two were even more impressed.
Finally, the third samurai steps up as a third fly comes in. He slices his sword through the air!!! But, nothing happens. The fly still lazily buzzes around the room. The third samurai just smirks and sheathes his blade.
“What are you so smug about?” The first samurai questions, “The fly is still flying around the room.”
“Yes of course,” The third samurai answers, “But he will never be able to have any children.”