Half of the time we're gone but we don't know where, and we don't know here.
--Simon & Garfunkel
Exploring suchness involves full awareness. That sounds simple, doesn't it? But what does it mean? Of what are we to become fully aware? Seeing things as they are-what is that supposed to mean?
It takes a lot of time and practice to begin to really get into this. It doesn't matter how open-minded or intelligent we are, it's just that these teachings run aground on the rocks of our usual way of thinking. Basically, the path of realization tends to go from no duality to duality and then back to no duality. It's like taking something apart to make a repair and then putting it back together. So while we would like to put it all together right away, it's important to take everything apart first, which can be a frustrating process at times.
Here is my humble answer to your confusion. For the record, I am not a monk or priest. I am not an advanced lay practitioner, nor do I possess any qualification for my opinion other than my own experience. I am not claiming this is the "best" or "truest" reply, and some may think it's rubbish. It very well might be. Ask me again in 6 months and I might give a far different answer, but here is my summary of my own "beginner's answer".
Imagine being in a flat, two-dimensional world, like a drawing on a sheet of paper. You would have length and width but no concept of "depth". In a similar fashion, we tend to focus on specific partitions of time and 3-D space, and we tend to have little or no concept of anything else. It's not a matter of anything magical or hidden, just a lack of awareness. So what is the "other" dimension or perception that is being overlooked?
Many Buddhists will answer according to the language of their own traditions. In the Mahayana Buddhist traditions, this ultimate dimension is called "suchness". The word itself doesn't tell us very much, does it? But it is related to another Buddhist concept, emptiness. Emptiness does not mean non-existence, or no existence, but rather lack of intrinsic existence. All forms have an origin, or birth, they continue to change, and then they have an ending, or death. The conditions of their birth, existence, and death are dependent on their circumstances in relation to other forms. This isn't radical, just everyday cause and effect. And in fact it is emptiness, or the fact that things are impermanent, that allows forms to arise in the first place. We break "form" and "emptiness" down into separate things for discussion but they are really two sides of the same coin. However, viewed from the perspective of the ultimate dimension, forms neither arise nor pass away. For this reason, in his writings the Dalai Lama often refers to the historical dimension, the world of cause and effect as we typically perceive it, as a contrast to the view from the ultimate dimension. Likewise, he tends to refer to the conventional self, i.e. Jane Smith or Max Power, versus the true or ultimate self.
Everything that is born (or comes to assume a particular form) will die (that form will change and eventually fall apart). However, what we might choose to call our true nature, or suchness, simply is. To be slightly repetitive, it is not born and it does not die. To be repetitive even more, we are not talking about some place far far away. Just everyday reality. Suchness is an illusive term because it cannot be confined to our normal ideas of time or space except in temporary conventional forms like stars, space dust, planets, and living beings. That's why you might read in a book from Buddhist traditions like the Dalai Lama about suchness in vague terms or even seemingly contradictory terms. But suchness is present as a part of everything you see and feel. So then really, while we create a duality of the "conventional" or "historical" dimension versus the "ultimate" dimension, they are not separate, just as we cannot truly separate "form" and "emptiness".
Just to be clear, the story isn't suggesting defeatism, or suicide, or euthanasia, etc. Instead it reflects the reaction many people have when hearing the advice of the Buddha. It sounds like madness. But all of us will die--we are all losing our grip on the root. Acceptance that death is a natural component of our conventional self is necessary if not easy. However, death does not trivialize the value of our individuality. It makes it all the more valuable. There will never be another person quite exactly like you, or me.
Everyone you meet is, in fact, unique, and the chance to be at any given place at any given time is also unique. Seen from this view every moment is a treasure, a once in eternity opportunity that will never come again. So each form, each rock and star and person, should be treated as the immeasurable treasure they are. As for passing away, then, it's like the end of a role or character. The actor doesn't cease, just the part played. In that sense, suchness puts on a costume and plays the role of Jack Smith or Jenny Killian, or the seat I am sitting in, or the bird outside my window. Each role is unique and wonderful, but the end of one role is merely the beginning of the next. So, then, on the one hand, one should treasure one's life and make the most of it, but on the other hand one should not be fearful about the fact that one day that particular part must give way to another.
When even partially grasped, this notion is liberating. One can get on with the business of living their life, to find the courage to be the person they were born to be, without hiding from or wasting precious time worrying over death. But as I wrote at the beginning, this is not a set of teachings which one simply fully accepts and understands all at once (my own understanding and true acceptance is as thin as a strand of silk). And that is how it ought to be. One should not just say "Oh well sure, if the Dalai Lama (or Thich Nat Hahn, or Pema Chondren, etc.) says so that must be right," and even if someone did that, they wouldn't really believe it or know it. One must awaken to such insight oneself, through investigation and practice.
So getting back to the opening question, what is it that we are striving to understand or perceive, it is just "how things are". As might be a little clearer, there is a reason for not giving a straightforward definition or description of suchness. Words are loaded with many connotations that will be taken differently by different people. This is true of all descriptions or attempts to define suchness. Suchness has not limits or boundaries. Different Buddhist traditions talk about it in their own way, but the trick is that the mind readily gets hung up on labels and descriptions. True suchness cannot be defined in conventional terms, but there are Buddhist schools which point to this common denominator in metaphors and analogies.
The Lotus Sutra traditions (especially Tien Tai and Nichiren Buddhism) use the imagery of that text to talk about the Eternal Buddha and the Dharma Body, which are glimpses of "suchness". In schools which emphasize the Heart Sutra, such as (Soto) Zen, people talk about suchness through negation: "all dharmas are forms of emptiness, not born, not destroyed; not tainted, not pure; not increasing, not decreasing; and so in emptiness there is no form, no feeling, no perception, no mental formations, no consciousness; no eyes, no ears, no nose, no tongue, no body, no mind; no color, no sound, no smell, no taste, no touch, no thought, no realm of sight and so forth until no end of consciousness, no ignorance, no end to ignorance and so forth until no old age and death and no end to old age and death, no suffering, no desire, no cessation, no path, no wisdom no attainment." All of the preceding terms are useful for describing reality at the conventional level but not at the ultimate level, hence their negation when pointing people to suchness.
Ironically, some people can even get hung up on these negations or on constructions like "both is and is not" and "neither is nor is not". It somehow sounds profound or mysterious, and it can be latched onto as some kind of pseudo-intellectual conclusion about these teachings. But just saying "it can't be described" or "it is all or nothing" is not the answer, those are just roadsigns, or as Buddhists are fond of saying, fingers pointing to the moon. Which is a nice segue into this final (very abbreviated) cautionary tale:
A monk who had been unable to realize enlightenment was finally able to do so when a visiting wise man raised his thumb. So, then to be clear, raising the thumb was not enlightenment, but it was a means to realize enlightenment for this monk. In my reading, it symbolizes a collection of teachings and practices, such as Pure Land or Tien Tai or Zen. So then whenever the monk was asked a profound question, he would raise his thumb, and people marveled at his enlightenment. One of the monk's students observed this and when the monk left town for a few weeks, the student mimicked his teacher. He would answer people by raising his thumb without any real understanding, just going through the motions he had observed from his teacher. When the monk returned he was told of this and called in his student for a private meeting. The monk asked the student what enlightenment was, and when the student raised his thumb the monk moved quickly with a knife and cut it off. The student screamed and cried, but the monk asked the student again, what is enlightenment. The student started to raise his thumb but it wasn't there--*flash*--the student became enlightened. Or as a professor of mine used to say, rules of thumb are meant to be cut off.
