There's a common misunderstanding of the concept of emptiness in Buddhism - namely that "Buddhists believe that things don't (really) exist" or, "Buddhists believe that nothing exists".
Emptiness really means 'empty of inherent existence'. In other words no phenomenon contains the reason for its existence within itself. All functioning phenomena arise from ever-changing relationships with other phenomena, including the minds of the observers.
The teachings on emptiness are concerned with HOW things exist, not IF and WHETHER things exist (UFO's Unicorns and Yetis) or WHY things exist (because God, The Devil or the Spaghetti Monster made them).
Language influences our thought. Let's consider how we use the words 'Exist(s), Existed and Existence'. Maybe 'Existence' itself is an arbitrary concept. Maybe 'Existence' is a convenient, conventional truth.
We don't normally say that an explosion exists or existed (though there's no logical reason not to say so). And we don't normally say that the universe occurs. Yet an explosion and the expanding universe are similar entities, just operating on different timescales.
From our point of view an explosion is a transitory event, but the universe is 'permanent'. An explosion happens, the universe exists.
We don't normally say that an eclipse exists, and we don't normally say that Stonehenge happens. Yet both phenomena are the temporary coming together of masses in a geometrical configuration. In one case sun, earth and moon in a straight line, in the other case, stones arranged in a circular pattern.
Relative to our lifetime an eclipse is a temporary phenomenon, whereas Stonehenge is more permanent (built to last 4000+ years).
But there is no absolute distinction between phenomena that exist and phenomena that occur or happen. The distinction is arbitrary, based on the following considerations:
(1) The universe consists of myriads of particles in a constant state of movement.
(2) These particles form aggregates which hang together for a time and then disintegrate.
(3) Aggregates that hang together for more than a substantial fraction of a human lifetime (eg a car) 'exist'. Aggregates that hang together for a tiny fraction of a human lifetime (eg a flash of lightning) 'happen' or 'occur' .
Yet although I think my car exists, it is actually a series of events. The car I arrived home in tonight is not the car I set out in this morning. It has rusted a bit. Its gears are worn. Its spark plugs are increasingly burnt. Its tyres are slightly less legal. Its windscreen-wipers are more knackered.
There's a Buddhist concept of 'subtle impermanence' which states that nothing whatsoever remains identical from one moment to the next.
So to say that something exists is ultimately an arbitrary statement. All we are saying is that its rate of disintegration is negligible on the timescale of our lifetime. In reality, all functioning phenomena are impermanent - it's just that some are more impermanent than others.
All 'things' are impermanent, and so all things are in reality processes. Things do not stay the same from one millisecond to the next. Anything composed of atoms is composed of parts in a constant state of flux. Existence is merely impermanence viewed in slow-motion.
Boxiness and trayfulness
To find the true and unchanging essence of a box you would have to find the unchanging essence of a process, which is a logical contradiction.
The nearest thing to finding a box-essence would be to say that these pieces of wood in this configuration perform the functions of a box. But that recognition comes entirely from your own mind (or from the collective minds of box-users).
It we were to cut the sides of a box down it would perform the functions of a tray.
If I say "I'll get a box to put this stuff in", then most people will understand that I'm going to fetch a container which performs the conventional function of a box, i.e. holds things. To do this it must have a bottom and at least three sides (like some chocolate boxes), though usually four. A lid is optional.
The box exists from causes and conditions (the box-maker, the wood or wood-pulp from which it is made, the trees, sunlight, acorn, soil, rain, lumberjacks etc.)
A box exists dependent on its parts (bottom and three or more sides).
The parts exist dependently on the box (otherwise they'd just be flat sheets of cardboard).
The box also exists because I and others decide to call it a box, not because of some inherent `boxiness' that all boxes have as a defining essence.
If it were a big cardboard box, and I cut a large L-shaped flap out of one side so it hinged like a door, then I could turn it upside down and it would be a child's play-house.
If I cut the sides of a wooden box down a centimeter at a time, then the box would get shallower and shallower. At some point the box would cease to exist and the tray would begin to exist. Or maybe the essence of `boxiness' would miraculously disappear and `trayfulness' would jump in.
Where does box end and tray start? I don't know. Maybe there's an EEC directive forbidding the construction of boxes with insufficiently high sides, or perhaps there's a Tray Descriptions Act. But whichever way, as well as existing in dependence on its parts, and on its causes and conditions, the box exists in dependence upon our minds (or the collective minds of the EEC Box-Standards Department) - imputing box over a certain collection of parts.
See also Buddhism and Process Philosophy
- Sean Robsville
Sunyata - the emptiness of all things
Inherent Existence in Buddhist Philosophy
Essentialism in Physics, Chemistry and Biology
The Four Seals of Dharma
Quantum Buddhism - Buddhist Particle Physics