The Emperor was really into Buddhism. He read everything he could get his hands on, he talked with philosophers and monks about it, he even tried writing his own discourses and Haiku. One day he heard that a famous Zen master was visiting the city. So, naturally, being the Emperor, he requested that the Master come to visit him at the Palace. He offered the Master a fine meal and afterwards performed a truly elegant tea ceremony. The whole time, the master is pretty much silent and peaceful, as you might expect from a Zen master - but the Emperor is biting his tongue. He wants to pick this guy's brains about Zen. So finally, as they are drinking their tea, he breaks the silence. "Master, according to Zen, what is the Self?"
The Master briefly looks up from his tea and says, "I do not know." Then he quietly continues sipping.
That's it! End of story! Now I wouldn't be surprised if the Emperor was a bit, shall we say, peeved. After all, this is a famous Zen master, a truly enlightened being. And he doesn't know what the self is? Come on! Now maybe he really wasn't all that enlightened. Maybe he really didn't know. At least he was being honest. Or maybe he did know, but he was doing the "Oh Humble" bit. Maybe that was the lesson for the Emperor - humility in the face of the Eternal Self. Or maybe his terse reply was intended to mean that no one can know what the self is, because the self is fundamentally unknowable, a mystery. It can't be spoken about or intellectualized. That's very Zen. Or, if we think about what he actually said - "I do not know" - he actually IS telling us that he does know something. He knows "NOT." Aha! Maybe that's it. The path to the self is through "NOT" - the process of negating, of stripping away, of undoing attachments. That's also very Zen.