In passing, that's how Sojun Roshi summed up the essence of the Soto tradition. That's right, in passing. The man is so full of insight, even his casual remarks open eyes.
But seriously... I don't remember if that was his thought or if he was quoting Suzuki Roshi, but either way he shared it with us.
What does it mean?
To me it is a reminder that we will never know everything. No experiences we accumulate will ever add up to the total experience of the universe. We say, "things are this way," and someone else replies, "yes, but.. to me it is like this." Those two words keep us searching, reminding us that life is dynamic. What is true in one instance may not be in another, but it does not deny it's veracity.
It also is a call to always try to see the other side, to always play devil's advocate. In this way we not only try to accept we don't know everything, but also we try to identify with those we view as opposed to us. We sometimes even see through our differences to see the similarities, giving us common ground to start understanding. We have to be positive and take the first step forward not harboring our grudge waiting for them to give in.
Both of these push further into the paradox of duality in a non-dual universe. Once we define something intellectually through dualistic discrimination, we simultaneously define both what it's not and what is not it. In physics we say a table is solid; we can touch it and our hand will not pass through. Modern science says, "yes, but.. on a subatomic level the solidity of the table disappears. Atoms are nothing but clouds of energy that have no substance at all." Light is another wonderful example, it functions as both particle and wave but is neither at the same time.
Any Zen doctrine we talk about relies on the duality of language to distinguish what is apparent truth and what is delusion. But to believe this truth is separate from what is not true is delusion. "Yes, that's true, but..."
As my practice has progressed, things have occurred to me that I have wanted to share. In order for me to receive help in understanding them, I have to be able to communicate them. But as I try to corral these ideas for my mind to brand with labels, I realize how futile it is. As soon as I have one idea strapped down, I see it's far more complicated. My label is empty and only addresses face values. I know this both intellectually and internally, but I still have to get it out somehow.
In order to clear away our delusion, we first have to examine it thoroughly. We learn its weaknesses and where it's strong. We figure out the rules that hold it together. In this way, the intellectualization is helpful and a necessary crutch. But we can't get attached to it because the scaffolding we construct to examine the structure is itself adding to the structure, deepening the problem. We penetrate to what our minds tell us is the truth and our hearts say, "yes, but... there's more." Only after our minds are satisfied can we commence with the serious business of stilling them.
What makes this uniquely Soto is that in practicing shikantaza, we don't try to harness the mind. As Uchiyama Roshi proposed, shikantaza is "opening the hand of thought." We relax, accept and observe. Rather than grab onto a koan like an ice cube and squeeze until the truth drips through our fingers, we let it sit and melt on its own. With our mind relaxed the defenses of our ego are down, leaving our hearts open to receive the truth which life may point to whether in the form of a koan, a casual remark, the sound of a drop of water, or a firm slap in the face.
In zazen we watch our thoughts come and go like clouds across the sky. This is an attempt to really take in the panorama, the big picture. This is contemplating "vastness/expansiveness" or the character "great/large" that Dogen mentions in the Tenzo Kyokun. If we allow our minds to be captured by a single thought and dragged along as if we were contemplating what image the shape of a certain cloud reminds us of, we don't see the other clouds, the rest of the universe.
Sitting zazen is practice like practicing a sport, or developing any other skill, but zazen off the cushion is practicing like a doctor practices medicine or a lawyer practices law. Sitting provides us with the "yes," and life provides the "but.." The Middle Way exists between the "yes" and the "but," while the affirmation is still true but before the negation establishes discrimination.
This is a tricky path to walk, but so incredibly simple at the same time. Just as always the only thing that we can do is what we can do, no more is possible and no less is permissible.