Sitting Physically

How does one sit Zazen?

Here I am talking about shikantaza or 'just sitting' in the spirit of Zen Masters Dogen and Hongzhi.   Of course, endless books articles and lectures has been done on this for centuries.  Admittedly I have read very little about Zen, but I have not found much about how to sit physically.  What do you do with your body while sitting?  What role does it play?
Most of what is written is about the attitude of the practitioner: what is her motivation?  What should she be trying to obtain?  What does she do with her mind?  Her thoughts?  More recently much has been written about zen and the emotional life, Zen and psychology.
There are ways to approach Sitting from different perspectives.  It is like peering into a jewel from different facets. They are all important avenues of investigation, and a seasoned practitioner will be familiar with all of them.
But we all have our tendencies.  Our personalities dictate if we look at our self and our Sitting practice by way of our mind, our emotions, our intellect, our our body.
I have tended to approached sitting physical.  For may years I did wrestle with my mind.  I tried to count my breaths, and for many more years tried to follow my breathing by bringing my concentration back to it.  And, of course, I like everyone else, am a deeply emotional being.  But the changing nature of emotions and thoughts has left me with a blend of disintrest and suspicion.  But the body is always present: the sensations from the body are real.  Lots of stuff is happening.  I know there are risks in practicing with the body: we can try to make these sensations into something they are not.  And there is the possibility I might see the body as something separate from a unified self.  But being aware of the body is an accessible mode of investigation in zen sitting, along with the mind and emotions.

So lets move onto grappling with how to use our body to sit?  What do we do with it?  This is an important question.  Dogen was very passionate about sitting, and Zen has traditionally emphasized the posture in sitting.   Dogen instructions on how to sit, the Fukanzazengi, is chanted frequently at all the zen center I have been to, and a frequent topic for lectures.  However I can not recall any lectures about Dogens thoughts about how to sit.  This despite the fact that  Dogen devoted about a quarter of the Fukanzazengi on how to physically sit!  It's also quite surprising that although Dogen is held in high regard, how many actually practice what he instructed?   Very very rarely.    

 We also have instructions from our current teachers.  We were all given instructions when we began.  But how often are we given updates, reminders or corrections?  Extremely rarely.  Oh, occasionally our teachers will admonish us "Don't move!"  or "Sit up straight!"  Once durring a sesshin I attended at the San Francisco Zen Center two teachers openly argued in the middle of a sitting about whether it was correct to either "tuck the chin" or "imagine a string, tied to the crown of the head was being pulled up".
They could not agree.  And I have heard encouragements to sit in full lotus.  But in my 30+ years of sitting that it about it for instructions.  I've listened to hundreds of hours of Zen lectures and basically nothing about how to physically sit.  Is your experience different?

So how we sit is very important.  And we have ancient instructions that how we use our bodies in sitting but we don't pay it much heed.  Modern teachers have little to say on the subject.  Do we have more modern instructions?  Has science or western thought anything to add?

This blog is an update on instructions can we give ourself on how to sit.  How do we physically sit?  What is the Yoga of Zen?