One of the most difficult teachings in Buddhism is the one on emptiness. The Sanskrit term for this is “sunyata” (I don’t want to bother with the diacritical marks, so if you like to know how the diacritical marks are to be applied on this word and other Sanskrit or Pali terms in my posts, you have to search elsewhere. 🙂 ) Basically this says that no thing has ‘inherent existence.’ A thing is what it is simply because it is we who impute characteristics to it so that it fits with our conceptualization of what that thing is. In plain English, a thing is what it is because we say that it is so, because it fits with our description of that particular thing.
For example, a table is what it is because it has certain shapes — four legs, flat top, and so on. But it is we who say that characteristics such as having four legs, flat top etc. are those of a table. It is we who say “this is a table.” From their own side (that is, without us who does the conceptualizing and name calling) this particular appearance is just plain “nothing.” It is “nothing” not because it is an apparition, as if it were a hologram shown to us by some fiendish scientists, but because whatever characteristics it has that fit it into certain categories such as being a table, is our own work as language user. This I think pretty much captures what ’emptiness’ means. The table is empty of its inherent characteristics, or inherent substance that makes it a table and not, say, a balloon.
Nagarjuna, following the Buddha’s teaching, says that everything whatsoever is empty. So long as it is a thing at all, it is empty. Genuinely realizing this truth is a key element in entering and progressing along the Path to Liberation, or nirvana. All kinds of sufferings arise because of the mistaken belief that things can stay the same and keep their identities. This always fail because there is simply no identity that a thing can keep.
But does this mean that, if all human beings all of a sudden vanish, then all things will vanish also? One is reminded of Berkeley who says just about the same thing. Well, it is not a matter of physical causation where the disappearance of one thing causes a disappearance of another. Things are much deeper than that. Buddhism is centered around human suffering and how to get rid of it. It does not presuppose the distinction between self and other, or the subjective and the objective, as does science. If you have the subject/object distinction, then it is straightforward to see that the disappearance of the subject has nothing to do with the object. But if you don’t have the distinction, then there is no basis on which you will be absolutely certain that objective reality will continue to exist without subjective thought. When the distinction is done away with, one does not separate between the two. So it is not the matter of the subject affecting the object, or vice versa. There is no subject, and no object to affect each other.
What this means is that when Nagarjuna says that it is human (or the conceptualizer’s) imputation that explains why a thing exists, this should not be taken to mean that the conceptualization causes things to exist or to cease to exist. But it is the conceptualization that brings the thing up to consciousness so that it is cognized as a table, a rock, or whatever. WHen the practitioner genuinely and deeply sees that things do not have their own inherent identity, then he is “liberated” in the sense tht all the causes and conditions leading to suffering will be totally eliminated.