There are, generally speaking, two ways to model enlightenment. One way involves what happens in the body, while the other describes changes in the content of the mind. We can refer to these two contrasting modeling styles as physio-energetic and psychological, respectively. While this kind of artificial duality is simplistic, it is useful in understanding and creating effective models. An effective model is one that both describes the experience of enlightened people at the various levels and predicts the experience of those who are working toward enlightenment.
A Physio-energetic Model
An example of a purely physio-energetic model would be a modified Theravada Buddhist model that describes observable phenomena, without regard to what a yogi thinks. For example, you might say that at some point a yogi experiences solid physical pain and clear, bright, pinpoint itches. With continued practice, the pain or itch breaks up into a rapidly changing experience of tingling, strobing, and/or vibration. I have just described the 3rd and 4th ñanas of the Theravada model, without any reference to what the yogi thinks about his experience. We could go on to say that the yogi feels cool tingling on the skin and what seems to be a descending flow of energy in the body (5th ñana). Soon thereafter, he feels discordant pulsing and vibrating in various parts of the body as well as unpleasant mental vibrations. These vibrations happen all at once, at various frequencies and levels of intensity, so that the overall effect is similar to that of jarring, dissonant music. This corresponds to the 10th ñana, Knowledge of Re-observation. Later, the vibrations become smooth and pleasant, the field of attention is panoramic and meditation becomes effortless (11th ñana, Knowledge of Equanimity.)
At no point in the presentation of this physio-energetic model has it been necessary to resort to the yogi’s thought process. This is in direct contrast to a psychological model, which is all about what a yogi thinks.
A Psychological Model
My favorite psychological model is that of the “Five Ranks of Tozan.” According to this system, a yogi will eventually come to the point where he can see in real time that there “aren’t two things;” all of experience is an undivided whole, permeated by and not other than awareness. At this stage, the yogi is officially enlightened. But his understanding is limited, as he is ignoring the fact that, although there aren’t two things, most people experience life as divided into thoughts of self and other. The enlightened yogi of the Third Rank can temporarily hold himself above the petty concerns of daily life, but has isolated himself from those who do not share his advanced vision. Although he can be a great inspiration to others who seek to emulate his detachment, he cannot relate to them on the most basic human level, a level which frankly requires the perception of duality. The Third Rank yogi is manifesting the notorious “stink of enlightenment” for all to see.
At some point, the enlightened Third Rank yogi, who has become accustomed to thinking of himself as unaffected by trivial human concerns may come to the rude awakening that he is still walking around in a human body, and thus subject to karma. He will step in a big bucket of dukkha and be unceremoniously ejected from his throne. This is the fall from grace, the Fourth Rank of Tozan. He will feel humble and human, and seek to pick up the tattered threads of his life.
After living as an ordinary chump for some period of time, the yogi may find that although he cannot escape his own karma, he is still infinitely better off than he was before his enlightenment. He still has access to the glorious non-duality of the Third Rank. He can manifest it at will, and finds that, if wielded skillfully, the stink of enlightenment tempered by the humility of the fall can be of great benefit to others. He realizes that there is nothing left to do with his life but to help “others” discover what he has learned. He consciously chooses to spend his time pretending to be “other,” for the benefit of those around him. He has reached the Fifth Rank of Tozan, the ideal of Zen Budhism.
Notice that throughout the explication of the five ranks it was not necessary to refer to any physio-energetic phenomenon whatsoever. The five ranks model deals exclusively with what is going on in the yogi’s mind. This is a purely psychological model.
It is, of course, possible to combine aspects of the physio-energetic and psychological models in an effort to provide a more complete picture of the yogi’s progress. The Theravada model of jhanas and ñanas is one such hybrid. The insight knowledges (ñanas) are described by Mahasi Sayadaw and others using both physical and psychological language. The 4th ñana (Knowledge of the Arising and Passing Away of Phenomena), for example, is characterized by subtle vibrations, the perception of lights, a “happiness unknown to men and gods,” and feelings of unity. This kind of hybridization works well up to a point, and provides a more comprehensive description of the stages than either the physio-energetic or psychological models can do in isolation. But, while this kind of modeling does an excellent job of describing the insight knowledges, it fails to capture the overall trajectory of the process of enlightenment. In other words, to use Theravada Buddhist language, the hybrid model does not work across Paths.
The Problem with Hybrid Models
It is tempting to create a model describing what a typical yogi is able to “see” at each of the Four Paths of Enlightenment. You might, for example, say that a sotappana (First Path yogi) can see w, a sakadagami (Second Path yogi) can see x, an anagami (Third Path yogi) can y, and an arahat (Fourth Path yogi) can see z. Unfortunately, there are too many instances of sotapannas who can see y and arahats who cannot see x. To give a concrete example, we may define sakadagami as someone who can clearly see the cycling of the insight knowledges in his daily life. While this is likely true of someone who has trained in vipassana and been exposed to the concepts and maps that describe these cycles, it is clear that some who have progressed well beyond this stage and have even gone on to the level of arahat do not see these cycles. What to do with data that does not fit the model? We are now in the uncomfortable position of either ignoring inconvenient data or completely overhauling the model. Another example is the pre-Stream Enterer who can “see emptiness in real time,” an ability that is sometimes associated with anagamis (3rd Path). The more we ask around, the more we find people who do not behave as our model would have them behave.
My latest thinking is that we need to do a lot more research and investigation before we can confidently build a model that integrates physio-energetic and psychological phenomena across the whole spectrum of enlightenment. Meanwhile, we should be hesitant use hybrid models to draw conclusions about the relative enlightenment of others, particularly when they are trained in a tradition other than our own.