Meditation teaches you the power of your perceptions. You come to see how the labels you apply to things, the images with which you visualize things, have a huge influence over what you see, how they can weigh you down with suffering and stress. As the meditation develops, though, it gives you the tools you need to gain freedom from that influence.

In the beginning, when you first notice the power of perception, you can easily feel overwhelmed by how pervasive it is. Suppose you're focusing on the breath. There comes a point when you begin to wonder whether you're focusing on the breath itself or on your idea of the breath. Once this question arises, the normal reaction is to try to get around the idea to the raw sensation behind it. But if you're really sensitive as you do this, you'll notice that you're simply replacing one caricature of the breath with another, more subtle one. Even the raw sensation of breathing is shaped by how you conceptualize raw sensation. No matter how hard you try to pin down an unfiltered experience of breathing, you still find it shaped by your idea of what breathing actually is. The more you pursue the reality of the breath, the more it recedes like a mirage.

The trick here is to turn this fact to your advantage. After all, you're not meditating to get to the breath. You're meditating to understand the processes leading to suffering so that you can put an end to them. The way you relate to your perceptions is part of these processes, so that's what you want to see. You have to treat your experience of the breath, not as an end in itself, but as a tool for understanding the role of perception in creating suffering and stress.

You do this by de-perception: questioning your assumptions about breathing, deliberately changing those assumptions, and observing what happens as a result. Now, without the proper context, de-perception could easily wander off into random abstractions. So you take the practice of concentration as your context, providing de-perception both with a general direction and with particular tasks that force it to bump up against the operative assumptions that actually shape your experience of the present.

The general direction lies in trying to bring the mind to deeper and more long-lasting levels of stillness so as to eliminate more and more subtle levels of stress. You're not trying to prove which perceptions of the breath depict it most truly, but simply which ones work best in which situations for eliminating stress. The objectivity you're looking for is not the objectivity of the breath, but the objectivity of cause and effect.

The particular tasks that teach you these lessons begin with the task of trying to get the mind to stay comfortably focused for long periods of time on the breath — and right there you run into two operative assumptions: What does it mean to breathe? What does it mean to be focused?

It's common to think of the breath as the air passing in and out through the nose, and this can be a useful perception to start with. Use whatever blatant sensations you associate with that perception as a means of establishing mindfulness, developing alertness, and getting the mind to grow still. But as your attention gets more refined, you may find that level of breath becoming too faint to detect. So try thinking of the breath instead as the energy flow in the body, as a full body process.

Then make that experience as comfortable as possible. If you feel any blockage or obstruction in the breathing, see what you can do to dissolve those feelings. Are you doing anything to create them? If you can catch yourself creating them, then it's easy to let them dissolve. And what would make you create them aside from your preconceived notions of how the mechanics of breathing have to work? So question those notions: Where does the breath come into the body? Does it come in only through the nose and mouth? Does the body have to pull the breath in? If so, which sensations do the pulling? Which sensations get pulled? Where does the pulling begin? And where is the breath pulled from? Which parts have the breath, and which ones don't? When you feel a sensation of blockage, which side of the sensation are you on?

These questions may sound strange, but many times your pre-verbal assumptions about the body are strange as well. Only when you confront them head-on with strange questions can you bring them to light. And only when you see them clearly can you replace them with alternative concepts.

So once you catch yourself breathing uncomfortably in line with a particular assumption, turn it around to see what sensations the new assumption highlights. Try staying with those sensations as long as you can, to test them. If, compared to your earlier sensations associated with the breath, they're easier to stay with, if they provide a more solid and spacious grounding for concentration, the assumption that drew them to your attention is a useful new tool in your meditation. If the new sensations aren't helpful in that way, you can throw the new tool aside.

For example, if you have a sense of being on one side of a blockage, try thinking of being on the other side. Try being on both. Think of the breath as coming into the body, not through the nose or mouth, but through the middle of the chest, the back of the neck, every pore of your skin, any spot that helps reduce the felt need to push and pull.

Or start questioning the need to push and pull at all. Do you feel that your immediate experience of the body is of the solid parts, and that they have to manage the mechanics of breathing, which is secondary? What happens if you conceive your immediate experience of the body in a different way, as a field of primary breath energy, with the solidity simply a label attached to certain aspects of the breath? Whatever you experience as a primary body sensation, think of it as already breath, without your having to do anything more to it. How does that affect the level of stress and strain in the breathing?

And what about the act of staying focused? How do you conceive that? Is it behind the breath? Surrounded by breath? To what extent does your mental picture of focusing help or hinder the ease and solidity of your concentration? For instance, you may find that you think of the mind as being in one part of the body and not in others. What do you do when you focus attention on another part? Does the mind leave its home base — say, in the head — to go there, or does the other part have to be brought into the head? What kind of tension does this create? What happens if you think of awareness already being in that other part? What happens when you turn things around entirely: instead of the mind's being in the body, see what stress is eliminated when you think of the body as surrounded by a pre-existing field of awareness.

When you ask questions like this and gain favorable results, the mind can settle down into deeper and deeper levels of solidity. You eliminate unnecessary tension and stress in your focus, finding ways of feeling more and more at home, at ease, in the experience of the present.

Once the mind is settled down, give it time to stay there. Don't be in too great a hurry to move on. Here the questions are, "Which parts of the process were necessary to focus in? Which can now be let go? Which do you have to hold onto in order to maintain this focus?" Tuning into the right level of awareness is one process; staying there is another. When you learn how to maintain your sense of stillness, try to keep it going in all situations. What do you discover gets in the way? Is it your own resistance to disturbances? Can you make your stillness so porous that disturbances can go through without running into anything, without knocking your center off balance?

As you get more and more absorbed in exploring these issues, concentration becomes less a battle against disturbance and more an opportunity for inner exploration. And without even thinking about them, you're developing the four bases of success: the desire to understand things, the persistence that keeps after your exploration, the close attention you're paying to cause and effect, and the ingenuity you're putting into framing the questions you ask. All these qualities contribute to concentration, help it get settled, get solid, get clear.

At the same time, they foster discernment. The Buddha once said that the test for a person's discernment is how he or she frames a question and tries to answer it. Thus to foster discernment, you can't simply stick to pre-set directions in your meditation. You have to give yourself practice in framing questions and testing the karma of those questions by looking for their results.

Ultimately, when you reach a perception of the breath that allows the sensations of in-and-out breathing to grow still, you can start questioning more subtle perceptions of the body. It's like tuning into a radio station. If your receiver isn't precisely tuned to the frequency of the signal, the static interferes with the subtleties of whatever is being transmitted. But when you're precisely tuned, every nuance comes through. The same with your sensation of the body: when the movements of the breath grow still, the more subtle nuances of how perception interacts with physical sensation come to the fore. The body seems like a mist of atomic sensations, and you can begin to see how your perceptions interact with that mist. To what extent is the shape of the body inherent in the mist? To what extent is it intentional — something added? What happens when you drop the intention to create that shape? Can you focus on the space between the droplets in the mist? What happens then? Can you stay there? What happens when you drop the perception of space and focus on the knowing? Can you stay there? What happens when you drop the oneness of the knowing? Can you stay there? What happens when you try to stop labeling anything at all?

As you settle into these more formless states, it's important that you not lose sight of your purpose in tuning into them. You're here to understand suffering, not to over-interpret what you experience. Say, for instance, that you settle into an enveloping sense of space or consciousness. From there, it's easy to assume that you've reached the primordial awareness, the ground of being, from which all things emerge, to which they all return, and which is essentially untouched by the whole process of emerging and returning. You might take descriptions of the Unconditioned and apply them to what you're experiencing. If you're abiding in a state of neither perception nor non-perception, it's easy to see it as a non-abiding, devoid of distinctions between perceiver and perceived, for mental activity is so attenuated as to be virtually imperceptible. Struck with the apparent effortlessness of the state, you may feel that you've gone beyond passion, aversion, and delusion simply by regarding them as unreal. If you latch onto an assumption like this, you can easily think that you've reached the end of the path before your work is really done.

Your only protection here is to regard these assumptions as forms of perception, and to dismantle them as well. And here is where the four noble truths prove their worth, as tools for dismantling any assumption by detecting the stress that accompanies it. Ask if there's still some subtle stress in the concentration that has become your dwelling place. What goes along with that stress? What vagrant movements in the mind are creating it? What persistent movements in the mind are creating it? You have to watch for both.

In this way you come face to face with the perceptions that keep even the most subtle states of concentration going. And you see that even they are stressful. If you replace them with other perceptions, though, you'll simply exchange one type of stress for another. It's as if your ascending levels of concentration have brought you to the top of a flag pole. You look down and see aging, illness, and death coming up the pole, in pursuit. You've exhausted all the options that perception can offer, so what are you going to do? You can't just stay where you are. Your only option is to release your grip. And if you're letting go fully, you let go of gravity, too.