It is interesting to note that the similar concept of emptiness didn't appear in the realm of Western thought and science until the middle of this century. It was only with the advent of cybernetics, and its immediate branches, the information and communication theories, that we have finally arrived at similar conclusions. The reason for that probably lies in the fact that Western civilization has been, in general, preoccupied for the longest time with the study of solid bodies and impacts (a study that reached its peak in the classical Newtonian picture of the world). The epistemological revolution brought upon us by the discovery of the principles of information theory has turned many of our deeply ingrained concepts and beliefs systems upside down. As a society, we are only now starting to feel the far reaching effects this revolution will have in the shaping of our lives (witness the disrupting and at the same time liberating effects that the emerging Internet information technology is beginning to exhibit at the end of the twentieth century).
What's so special about the information theory that makes it stand out and exhibit such ground sweeping overall effects? The very idea of the information is such a radical departure from the time-honored concepts of the Western thought, that it is impossible to expect it not to have a profound impact on every aspect of our lives. When we take a closer look at the formal definition of information, it becomes immediately clear whence does the radical nature of this concept come form: the information, we are told, is characterized by being zero-dimensional. Having no dimension whatsoever, the information does not occupy any space or time. It is therefore not a thing.
We must quickly point out here that, although the information is not a thing, it is not nothing. The descriptive definition of the information states that it is "a difference that makes a difference". In other words, a bit (no pun intended) of dimensionless, intangible "something" has the power to make a difference among the manifested things. The information is empty, shapeless, and yet it manages to shape the non-empty objects. This concept is a big departure from the traditional Occidental world view in which the universe is depicted as a giant mechanism where objects with different trajectories exercise impact on the surrounding objects, thus causing them to change, and in turn to cause further impact and further changes. There was no room in such a picture for emptiness to come in and to start influencing and causing things to happen (for a nice introduction to such concepts, the reader may find it useful to review Gregory Bateson's article "Cybernetic Explanation", published in the American Behavioral Scientist, Vol. 10, No. 8, April 1967, pp. 29-32, and reprinted in his widely popular book "Steps To An Ecology Of Mind", pp. 399-410).
What is particularly surprising to any casual observer with regards to the information theory and cybernetics, is how late in the game it came to be discovered. Given the incredible propensity for non-dogmatic and exploratory thinking that has been the hallmark of Western thought for thousands of years, one is at a loss when it comes to explaining why hasn't such a groundbreaking concept been tackled much earlier. Of course, once the information theory got established and popularized, it was easy for everybody to see how simple and yet how powerful that idea is. But, why did it take more than 2,500 years before we became even aware of it?
Regardless of the reasons for such massive (and inexplicable) holdup, we have seen that it took less than fifty years for this discipline to flourish and to penetrate everywhere. One of the positive consequences of this revolution is that it had opened many minds to the fact that there are subtle, intangible factors at play that can drastically modify everything in our lives. The hard materialism that our culture used to be steeped in since it had embraced the advent of scientific reasoning, is slowly giving way to the softer, less formal brand of materialistic thinking. This general trend, coupled with the whole class of discoveries made by the hard sciences (the sub-atomic physics and the astro-physics) has made an indelible dent in the edifice of soulless materialism. Nowadays, it becomes a challenge to defend the hard core materialistic stance based on scientific facts, because the very science that has inaugurated this reasoning is now revealing that, as we peel off the ever smaller layers of subatomic particles, we end up finding the absence of any matter whatsoever. In other words, we have descended to the emptiness itself.
When we move from the world of blind, deaf and dumb objects (the mechanical universe) into the world of communication, where these objects suddenly become sensitive and respond to each other without being forced by the dynamics of the mechanical impacts, we discover the same fundamental thing -- everything is devoid of its essential nature. As R.L. Stevenson put it, "anything can stand for anything else, and a horse-shoe will do just fine." Thus, in the animal kingdom for example, when baring its fangs upon encountering other animals, a wolf may be trying to say: "no, I will not attack you; let's play", or he may be trying to say: "caution! if you get any closer, I will attack you!" The meaning of this act of communication is totally dependent on the context where the action is taking place. And the context itself is dependent on other contexts, and so on. In this entire huge network of dependencies and correlations, there is nowhere a thing to be found that exhibits its own nature that has nothing to do with all the other players.
The above realization of emptiness (i.e. voidness of one's own essential nature) reveals the essence of the emptiness which we could denote as horizontal emptiness. Again, because we have arrived at this insight by comparing the phenomena that are manifested at the same level of abstraction, we consider such realization to be of inferior nature. Similar to our previous discoveries of what comprises a superior, or vertical insight, we can expect that only if we could arrive at an insight of emptiness that results from encompassing different levels of abstraction, could we really penetrate to the superior realm of the true emptiness -- the vertical emptiness.
We have seen that, in the world of communications,
a certain action can be employed to stand for some other action (e.g. waving
a white flag denotes a ceasefire, etc.) What is also interesting is how
an absence of action (i.e. emptiness) can also stand for some other action
(e.g. someone receives a message from his wife; he doesn't call her back;
that triggers an angry action coming from his wife). This coupling of emptiness
(certain communicational gesture that is in itself devoid of any self-essence)
with the absence of emptiness (an implicit message sent out by the act
of refusal to partake in the network of inter-dependent acts) is what we
may use to point to the vertical emptiness. It is in a way closely tied
with the above discussed vertical dualism (revealing the self-referential
nature of two levels of abstraction -- action on one level, and absence
of action in response to the original action on another level).