Shikantaza

"Just sitting" is the term that Rujing used for "silent illumination" or "silent reflection"[note 1] (Chinese mòzhào 默照; Japanese mokushō) which may be understood as the integrated practice of shamatha (calming the mind) and vipashyana (insightful contemplation), and was the hallmark of the Chinese Caodong school of Chan.[12]

It is not merely just the union of calming and insight, which had already been developed within the Tiantai Buddhist tradition in medieval China. Rather, it is a description of the natural essence and function of the mind. In this sense, it can be traced back to the earliest Chan teachings of Bodhidharma.[13]

The first Chan teacher to articulate silent illumination was the Caodong master Hongzhi Zhengjue (1091—1157), who wrote an inscription entitled "silent illumination meditation" (Mokushō zen 默照禅 or Mòzhào chán 默照禪).[14] According to Taigen Dan Leighton, this practice is a "nondual objectless meditation" which:

...involves withdrawal from exclusive focus on a particular sensory or mental object to allow intent apprehension of all phenomena as a unified totality. This objectless meditation aims at a radical, refined nondualism that does not grasp at any of the highly subtle distinctions to which our familiar mental workings are prone and which estranges us from our experience. Such subject-object dichotomization is understood as artificial, a fabrication. Silent illumination is also objectless in the sense of not seeking after specific limited goals. The ultimate purpose of spiritual practice, universally awakened heart/mind, cannot be set apart from our own inherent being and our immediate, moment-to-moment awareness.[15]

A. Charles Muller explains that this method, which involved seeking enlightened wisdom through complete stillness of the mind, became "the main practice of the Sōtō Zen school, where Dōgen characterized it by such terms of as 'just sitting' 只管打坐.".[16]

Shikantaza's origins can also be traced back to silent illumination. However, some teachers see it as different from the teachings of Hongzhi Zhengjue in terms of practice and theory.[17]

In the thirteenth century, Dōgen Zenji who introduced the Soto School in Japan, used much of Hongzhi's writings on silent illumination to help shed light on what he termed "shikantaza". From then on the practice of shikantaza has been primarily associated with the Soto school. While silent illumination is in theory a "methodless method", it is important to realize that, the Dogen practice of shikantaza "took a somewhat different approach."[18]

The Chinese Chán Master Shengyen has stated, that shikantaza is similar to silent illumination.[13][19]

Master Shengyen explains the meaning of the term in this way:

This “just sitting” in Chinese is zhiguan dazuo. Literally, this means “just mind sitting.” Some of you are familiar with the Japanese transliteration, shikantaza. It has the flavor of “Just mind your own business.” What business? The business of minding yourself just sitting. At least, you should be clear that you're sitting. “Mind yourself just sitting” entails knowing that your body is sitting there. This does not mean minding a particular part of your body or getting involved in a particular sensation. Instead, your whole body, your whole being is sitting there.[20]^:94

According to Merv Fowler, shikantaza is described best as,

quiet sitting in open awareness, reflecting directly the reality of life.[21]

Shikantaza is often termed a goalless meditation in quiet awareness,

not working on any koan, or counting the breath. It is an alert condition, performed erect, with no trace of sluggishness or drowsiness.[22]

In his work Fukan zazengi, Dogen writes of,

Finding a clean, dry place, if possible cool in summer and warm in winter. He goes on to describe the use of a zafu, or small round pillow one sits upon, and the zabuton, or larger square, flat cushion under the zafu, which supports the ankles and knees. He then describes the basic posture—sitting erect, with hands in the lap, eyes cast downward—as 'the method used by all Buddha ancestors of Zen.'"[23]

Fred Reinhard Dallmayr writes,

Regarding practice, Dogen counseled a distinctly nonattached or nonclinging kind of action, that is, an activity completely unconcerned with benefits or the accomplishment of ulterior goals: the activity of 'just sitting' or 'nothing-but-sitting' (shikantaza) whereby self-seeking is set aside in a manner resembling a resolute 'dropping off of body and mind.'[24]

According to Master Shengyen,

While you are practicing just sitting, be clear about everything going on in your mind. Whatever you feel, be aware of it, but never abandon the awareness of your whole body sitting there. Shikantaza is not sitting with nothing to do; it is a very demanding practice, requiring diligence as well as alertness. If your practice goes well, you will experience the 'dropping off' of sensations and thoughts. You need to stay with it and begin to take the whole environment as your body. Whatever enters the door of your senses becomes one totality, extending from your body to the whole environment. This is silent illumination."[25]

The modern Japanese Zen master, Haku'un Ryōko Yasutani says:

Shikantaza is the mind of someone facing death. Let us imagine that you are engaged in a duel of swordsmanship of the kind that used to take place in ancient Japan. As you face your opponent you are unceasingly watchful, set, ready. Were you to relax your vigilance even momentarily, you would be cut down instantly. A crowd gathers to see the fight. Since you are not blind you see them from the corner of your eye, and since you are not deaf you hear them. But not for an instant is your mind captured by these impressions.[26]

In contrast to this opinion, some of the Zen masters in Loori's book The Art of Just Sitting deride Yasutani's description, giving their own version as the right or correct way to do shikantaza.[27]

Concerning the Rinzai school, John Daido Loori writes,

..[A]fter students finish koan study, they then take up the practice of shikantaza.[28]

Haku'un Yasutani agrees, stating,

The Rinzai and Obaku Schools emphasize koan study; the Soto school emphasizes shikantaza. But even when koan study is stressed, shikantaza is not abandoned. All of the great masters of these three schools emphasize the importance of shikantaza."[29]

In Japan, vipassana and shamatha are sometimes used in addition to shikantaza as complementary practices.[30]