"One of the points in the traditional Buddhist way of viewing the question of what reality is or what truth is, is that in fact we cannot perceive reality, we cannot perceive truth. This is not to say that there is no reality or truth, but rather that whatever we perceive, if we happen to perceive anything, we see in accordance with some particular language or approach, and we color it with our own styles and ways of looking at things.
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The nonexistence of ego is not a philosophical matter, but simply a matter of perception. Perception is unable to trace back its existence {to an origin}, so it becomes just sheer energy, without a beginner of the perception and without any substance. It is just simple perception. Perception on that level has three aspects.
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The first is perception as experience. In this case, experience does not refer to the experience of self-confirmation, but to experience in the sense of things as they are. White is white, black is black, and so forth.
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Then there is {the second aspect}, the perception of emptiness, which is the absence of things as they are. Things have their room; things always come along with a certain sense of room, of space. Even though they may appear within the complexities of the overcrowdedness of experience, they provide their own space within the overcrowdedness. Actually, overcrowdedness and room are the same thing; overcrowdedness is room in some sense. This is because there is movement involved, because there is dance and play involved. At the same time, there is a shifty and intangible quality, and because of that the whole thing is very lucid.
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There is experience, then space or emptiness, and then the final aspect, which is called luminosity. Luminosity has nothing to do with bright visual light. It is a sense of sharp boundary and clarity. There is no theoretical or intellectual reference point for this, but in terms of ordinary experience, it is a sense of clarity, a sense of things being seen as they are, unmistakably.
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So there are these three aspects of perception: the sense of experience, the sense of emptiness, and the sense of luminosity. The point is that with that level of perception {that contains the three aspects}, one is able to see all the patterns of one’s life. Whether the patterns of one’s life are regarded as neurotic or enlightened, one is able to see them all clearly. That seems to be the beginning of some glimpse of the mandala perspective, the beginning of a glimpse of the five buddha energies."
- Chogyam Trungpa (1939 - 1987)
Orderly Chaos: The Mandala Principle