I would like to mention that the most important teaching of Master Rinzai is buji. This term appears more than twenty times in The Book of Rinzai, but there is no English word that reflects exactly what buji expresses.
Bu means no or negation. Ji is event, matter, action, phenomenon, affair, or thing. Literally, buji means to negate all ji. What does that mean? Life is ji. Getting old is ji. Sickness is ji. Passing away is also ji. In fact, from morning to night, we are ji itself. We have a tendency to think that by doing various practices (ji), we can reach a point where delusions disappear and there is nothing further to seek. This view is a deception. How could reality be altered by practice? Yet you may ask, if buji implies doing nothing, then why do we have to practice? Isn’t “doing nothing,” in the usual passive sense of the phrase, enough? At the same time, isn’t our very being one of ji? And isn’t our very being the source of all our problems and suffering? Can we negate or transcend our own limited being?
When we completely realize the true nature of the universe, what seems to be ji is in fact none other than buji. There is nothing to do, no matter how hard we try. From a slightly different perspective, the closest English word to buji is “now” or “as-it-is.” Right now, can you improve now-ness or as-it-is-ness? The answer is obviously no. At this very moment, can you or your circumstances be otherwise? When you understand that this present moment is all there is, you have no choice but to come to a radical acceptance. And it is this radical acceptance that is none other than true peace and composure. Buji means to be one with suchness, the unconditional nature of “let it be,” with nothing wanting, nothing superfluous.
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[But] I must mention one caution: in the Zen tradition, we often hear expressions such as “suchness” and “accept things as they are.” While these statements are true, they may be a bit misleading. There is an unspoken, underlying truth that things are changing moment by moment. Accepting suchness does not mean that no effort is necessary on your part. A spinning top appears to be stationary, despite being in motion. It is precisely this motion that keeps the top suspended upright. In much the same way, the man of buji is the busiest man, as he needs to change himself and improve himself moment by moment. This is the significance of our practice.