Take "It's raining," for example. What's the "it" in the sentence refer to? The sky? Well the sky doesn't rain. Okay, then how about the clouds? Well, technically rain is the liquid form of cloud vapor, so saying that clouds "rain" isn't quite accurate; they're really not separate. The truth is, in reality there is no subject performing the verb "rain."
The same goes for us. There is no central I controlling my thoughts and actions the same way that a driver steers a car. But that's how we think about this "self" most of the time--as if it's the agent behind all of our thoughts, words, and deeds.
But reality doesn't obey grammar.
Sure I have the sense that there is some me inside my head controlling my body and mind, but to return to my original point, that sense of I-ness is itself clinging. It's a mental contraction, the psychological equivalent of a muscle cramp.
And Zen is like a deep-tissue massage in our minds. It kneads out those cramps, revealing that there never was an I in the first place.
I find that Western Buddhists, being psychologically oriented as we are, tend to shy away from the Buddha's teaching of no-self. We're a bit apologetic when it comes to discussing the "self," opting to say things like "There is no independent, unchanging self," rather than looking the issue square in the eye.
To say self is like believing that a fist is really a noun, a thing, when in reality it can just as easily be seen as an action. Don't get me wrong: I'm not suggesting juggling grammatical terms, trading the term "noun" for "verb." That would be like adding delusion to delusion, swapping mud for clay.
I'm reading the Platform Sutra for a course I'm taking at the College of Zen Buddhist Studies, and in the text the Sixth Ancestor says that Zen is about getting beyond all views. Nouns, verbs, these are all conceptual constructs that we should avoid clinging to. It's fine to use language, as long as it doesn't use us.
The same goes for a self. Feeling afraid might be useful in order to protect me from danger, but I try my best not to believe that there's some real "I" in my head pushing buttons. Sure there's subjectivity, but that needn't entail a subject. Our sense of an I is really just a mental constriction like an asthma attack.
To test this, the next time you get angry, when your sense of self is at its strongest, investigate the emotion. Probe the muscular tension, the tightness in your chest, the flaring indignation. Then ask yourself where this experiencing self is?
You won't find it because there is no self experiencing the anger. In fact, it's the other way around; the anger produces the sense of self.
So how do we unclench that mental fist?
In Five Mountain Zen Order we ask the huatou, "What is this?" as often as we can. When I'm emptying the dishwasher, doing the laundry, and exercising, "What is this?"
The more and deeper we probe this essential question, the more honestly we can say, "Don't know." Under the lens of this delusion-dispelling question, the self, along with its concomitant battalion of concepts, evaporates. Since, after all, it was a phantom to begin with.
Where is this mysterious, elusive I? Like Bodhidharma answered Emperor Wu, we say, "Don't know." To borrow from Kosho Uchiyama, "Don't know" is the act of opening the hand of thought. I call it, unclenching the fist of I. Others call it No Mind. They're all the same thing.
No-self is not some special state; it's our original nature. Empty, free, clear, and bright. You don't have to practice Zen for thirty years to experience it. Why would you? It's your true nature.
But I've already said too much. Same, different, self, no-self, these are more ideas. To get to the truth, we need to let go of all concepts and views.
"What is this?"
Fist photo borrowed from Creative Commons flickr user ElvertBarnes, open hand from AmyZZZ1.