I have made concentration the core of my current practice for some time, but despite that, due to a constitutionally poor aptitude for it, am not familiar enough with how it works. So this thread will be an attempt to map out the concentration territory as I have experienced it, which I will add to based on my own practice. (Sort of a hybrid practice log / summary of notes, but I don't plan to regularly post details of particular sits.) Part of the goal is simply to provide a record that I can use, part is to share it with others who may also be interested in concentration, part is to get feedback from anyone who may have useful information to share.
I should make clear at the beginning that I am not aiming for any of the jhanas as described in MCTB, as those things seem to depend on aggravating the attention wave in a particular way, which I do not see value in. I believe that the jhanas described in the Pali suttas are entirely different (and am interested in those), and tentatively believe that the jhanas described in the commentary are "maximal" versions of those.
Here is my experience so far. If I begin by focusing on the sensation of breath at a particular spot (usually the rim of the nostrils, or, if constricting the throat while breathing, at the base of the throat), at first the mind is fairly uncooperative and continues to do things other than observe these areas, so it is helpful to put a bit of "effort" into keeping the particular location centered in experience.
During this process it is also helpful to generate a unique "sensation nimitta" which I believe the Vimuttimagga describes thus:
To the yogin who attends to the incoming breath with mind that is cleansed of the nine lesser defilements the image arises with a pleasant feeling similar to that which is produced in the action of spinning cotton or silk cotton. Also, it is likened to the pleasant feeling produced by a breeze. Thus in breathing in and out, air touches the nose or the lip and causes the setting-up of air perception mindfulness. This does not depend on colour or form. This is called the image. If the yogin develops the image and increases it at the nose-tip, between the eyebrows, on the forehead or establishes it in several places, he feels as if his head were filled with air.
There is a delicate balance between effort (which keeps the mind steady) and this sensation (which is repulsed by effort). Effort in particular, which generates a tension in the head, prevents the experience that is likened to one's head "filled with air" and which is related to this sensation.
As my mind steadies, effort can be actively reduced, and to the extent that I 1) reduce effort / relax, and 2) stay alert and continue to attend to the breath, the breath becomes less perturbed by the attention wave. What I mean is this: the attention wave is a tuning-out of sense-experience, and when it is present, it makes the sensation of breath appear to "ripple" or have "waves" or have outright gaps in it. As relaxation and effort increase (EDIT: typo; effort
decreases), if alertness is maintained, the perception of the breath becomes smoother and smoother.
During this process of "smoothing" the breath, there is a corresponding reduction of attention wave-related tensions in the body. During normal experience, it appears that there are myriad different tension experiences temporally stacked on top of each other, each one related to a kind of dreamy mental activity...I think of it as a "chorus of delusion"...but as the breath becomes smoother, these tension experiences fall away, leaving only a few voices and a perception of stillness. (However, tension experiences typically remain in the head at this point.)
When I have reached the point where there are very few tension experiences in the body (apart from the head), it seems common to experience the beginning of a rapid flickering of light. As I continue to attend to the sensation of breath, two things happen: residual tensions in the body continue to disappear, and the flickering of light is gradually replaced by a perception of "brightness" which is different from what one might see when looking at a real light through closed eyelids. I find this "brightness" difficult to explain. Previously I thought it was connected with piti / sukha, but I have found that it can arise just fine without it, and appears to be connected to the "smoothing" of the breath and the stilling of body tensions instead.
From this point, as I "smooth" the breath, the perception of brightness also becomes clearer (the visual flickering and the brightness seem analogous to the "waves" in the perception of breath), and it is possible to reach a state in which there are no or nearly no body tensions at all (apart from the head), a vast reduction in the experience of the attention wave (perceived as "vast stillness" / "quiet"), and a (nearly?) static perception of "brightness". I am not sure what to call this state, but it seems like a landmark of some kind. It may be "access concentration" according to the commentaries.
Bhante G:
...when samadhi is considered in its broader meaning it involves a wider range of reference than jhana. The Pali exegetical tradition recognizes three levels of samadhi: preliminary concentration (parikammasamadhi), which is produced as a result of the meditator's initial efforts to focus his mind on his meditation subject; access concentration (upacarasamadhi), marked by the suppression of the five hindrances, the manifestation of the jhana factors, and the appearance of a luminous mental replica of the meditation object called the counterpart sign (patibhaganimitta); and absorption concentration (appanasamadhi), the complete immersion of the mind in its object effected by the full maturation of the jhana factors.
In this state, the hindrances seem suppressed. (Sensual desire and ill will and restlessness seem connected with various tensions outside of the head, and those appear to be gone; tensions in the head appear to me to be some other kind of defilement, but I am not quite sure how to classify it.) The "brightness" may be the counterpart sign. Or, perhaps not; Culadasa (http://dharmatreasure.com/wp-content/uploads/2010/10/jhanas-and-mindfulness-handout.pdf) distinguishes the counterpart sign explicitly from the perception of light. However, Culadasa also says the perception of light is linked to piti, whereas I am certain that the phenomenon I am describing is not. So, the matter is unclear.
One of the main difficulties for me in attaining this state is that I cannot divert my attention to any tensions in the body in the process of obtaining it, even for a moment, because the act of doing that re-generates them and messes up my concentration. However, in this state, there is a fair bit of stability, and it is actually possible to look and notice the lack of tension. However, I cannot say for sure that there is actually no tension, or just a tiny indiscernible amount, because 1) if I look for too long, tension is re-generated, and 2) the act of looking for tension seems to require the existence of tension in some way, at least so far.
In general, the process of working up to this state is not linear, but more like two-steps-forward, one-step-back. Upon reaching higher and higher levels of "smoothness" in the breath, there is an instability caused by recognizing that, which quickly de-stabilizes the breath again. The process seems to be one in which the mind needs to slowly get accustomed to higher levels of stillness, which means I have to reach them and lose them many times before they "stick". However, once they "stick", they become a kind of baseline level of concentration for that meditation session.
In any case, from the highest level of concentration described above, many things are possible. The "actualizing jhanas" method (juxtaposing any attention wave thing with what isn't attention wave) seems to be very powerful. Simply sitting in that state seems to be useful. It also appears possible to deepen concentration by relaxing tensions in the head (associated with ceasing certain kinds of cognition). From past experience there is an "event horizon" around this point in which, once enough cognition stops, there is not enough remaining to destabilize concentration, and one gets sucked into a state that has no cognition nor sense experience, which, according to my best guess, is jhana according to the commentaries. However, though I have "fluked" that in the past, I have no idea how to get there intentionally.
Everything that is possible at a high level of concentration seems possible at a lower level of concentration, too; it's just more effective with more concentration. It seems that one can relax head tensions / cognition without relaxing body tensions first, but I need to experiment with that some more before describing it. (When trying to do it that way, it seems possible to fall into a kind of "zoned out" state if not careful.)
The relationship between the states of concentration I've described and the jhana factors is not so straightforward, and I need to experiment with that before saying more as well. But, overall, it seems that pleasure helps get concentration off the ground, but it is nonetheless possible (albeit hard) to reach the state that I hypothesize is "access concentration" without any pleasure at all.
Things I definitely don't understand but would like to find out about:
* whether there is any value in attending to perceptions of pleasure instead of the breath
* whether there is any value in attending to the "sensory nimitta" explicitly (it normally seems to be mixed with the breath in a hard-to-describe way)
* whether there is any value in attending to the perception of "brightness" explicitly
More posts in the future.