Occurs to me this morning that I can discuss why the lotus or half-lotus in terms of practice and verification:
The Patriarch asked, “Where do you come from?”
Nan-yueh answered, “From Mt. Sung”.
The Patriarch said, “What is it that comes like this?”
Nan-yueh replied, “To say anything would be wrong”.
The Patriarch said, “Then is it contingent on practice and verification?”
Nan-yueh said, “Practice and verification are not nonexistent, they are not to be defiled.”
(“Dogen’s Manuals of Zen Meditation”, by Carl Bielefeldt, pg 138)
Practice is something I do out of necessity, in seated meditation out of the necessity of breath and posture. Verification is something that I don’t do, something that happens without volition, that turns out to be the same as practice. That’s the way I experience practice and verification.
In the lotus, I am forced to realize the necessity of the movement of inhalation and exhalation and the posture, and in particular the location of mind that includes contact in the senses before comprehension from one instant to the next. Verification comes in as the location of mind sits the posture in an inhalation or exhalation.
In the half-lotus, I am forced to realize the necessity as in the lotus, but guess what!- it’s not as urgent.
Sitting in a chair, I am forced to realize the necessity, but usually without much urgency at all. Unless perhaps I have injuries that make such realization of necessity urgent in any posture.