For the vast majority of practicing Buddhists, the lifestyle is about practice--following common sense living patterns that are intended to remove the elements that hinder our ability to be happy, and to cultivate those that nurture happiness. We try to avoid hurting others, avoid bad habits, in order to be happier, and to help other people be happier.
The idea is that living in such a way will very gradually cause us to evolve out of the habit of suffering. For traditional Buddhists, it's believed that many lifetimes of such gradual evolution will eventually bring us to the brink of full awakening, or enlightenment.
In a relatively small corner of the Buddhist world, a somewhat mystical and esoteric corner, the focus is on View. The belief here is that one can come to enlightenment all at once, in this very lifetime, by opening one's mind suddenly to see the truth of how things are. Some forms of Zen practice fall into this corner, as do the Tantric Tibetan schools, such as Dzogchen. To become awakened here is said to be a matter of achieving permanent non-dual awareness, an awareness in which it is seen finally that observer (witness) and the observed phenomenon are not two, but are the same thing. It's here that you run into strange sayings, such as "Emptiness is Form; Form is Emptiness."
It is in this corner of Buddhism where you run into a term that is sometimes translated as "suchness," or "is-ness," or "thusness." I first ran across the term while reading Ken Wilber nearly 10 years ago now, but I didn't really begin to understand it at all until I began to study the Tibetan teachers from whom Wilber was borrowing his ideas. In particular, I would recommend Chogyam Trungpa, who elucidates these powerful ideas like no one else.
A vastly oversimplified explanation of "suchness" is that it is our state of mind when we flash to a genuine experience of non-dual awareness. At these moments, past and future cease to exist, and we are entirely within the absolute perfection of a moment. All striving is seen as pointless, since each moment is a perfect one. There is no goal to achieve; it was a delusion to have been pursuing a goal at all, since Buddha-nature is already ours. We are said to experience "one taste," in which observer not only merges with the observed, but understands that there was never any separation at all.
Trungpa describes these glimpses as "flashes," and points out that once experienced, the ongoing practice is to cultivate and stablize our ability to dwell within the flash of the awakened mind.
I had studied these ideas and contemplated them for quite a long time before I had the first such small flash of really understanding what these very smart people were talking about.
It occurred during a lecture I was attending at a local meditation center. That night, the teacher was elaborating on the nature of awareness, in particular talking about how to shift one's attention during a meditation sitting from the beginning object (in our case, the breath), gently onto the faculty of awareness. We talked for quite some time about this very important element of meditation practice: resting comfortably in bare awareness.
Then the teacher said "And it will be interesting to note that at no time is it possible to be aware of nothing. To be aware, is always to be aware of some thing, some phenomenon. Phenomenon, experience itself, is always connected to awareness. You cannot have awareness without an object. And vice versa, I suppose."
There was a common sense truth here that I saw, so simple that I was stunned to have missed it for so long. Of course awareness occurs only with an object, and this implied a reflexive truth: that all objects, all phenomenon, include awareness within their fabric. In all things, awareness is included. It is inherent in all phenomenon. It could be no other way. It's only our mistaken view that prevents us from joining into this cosmic awareness. In one writer's words, "you no longer look up and admire the sky. You become the sky."
In the years since, I have had other flashes, and I suppose its fair to say that the experiences both awe me and terrify me a little. Unlike the Dzogchen masters of Tibet, I'll almost certainly fail to fully awaken in this lifetime.
In my own rare and fleeting glimpses of non-dual suchness , my experience is of a complete dissolution of boundaries between self and object. But unlike what occurs in madness, this dissolution carries with it not annhilation of self, as we commonly fear, but a vast and natural expansion of self into a kind of grand awareness that is implicit in all things.
The paradox of progress in this kind of practice is that it's really not about achieving anything at all, but about systematically surrendering all the things that obstruct our genuine awareness. First and foremost among these obstructions is the terrible defense of the small self, sometimes called ego. It is this defense that fills our normal everyday life, which is exactly why we imagine that awakening is a difficult feat rather than wonderfully simple. Pretty much everything we thought we knew turns out to be a delusion.
Even with pitifully small experience, I would warn you that this is very serious practice that requires much discipline and fearlessness. It most definitely should not be viewed as some kind of shortcut for people too impatient to practice moral living. Expert teachers will tell you that you have to pretty much surrender everything you've believed about yourself to practice in this kind of way. After 10 years of rather serious study, I know just enough to be careful.