One of the most important philosophical insights in Buddhism comes from what is known as the theory of emptiness. At its heart is the deep recognition that there is a fundamental disparity between the way we perceive the world, including our own experience in it, and the way things actually are. In our day-to-day experience, we tend to relate to the world and to ourselves as if these entities possessed self-enclosed, definable, discrete and enduring reality.
For instance, if we examine our own conception of selfhood, we will find that we tend to believe in the presence of an essential core to our being, which characterises our individuality and identity as a discrete ego, independent of the physical and mental elements that constitute our existence. The philosophy of emptiness reveals that this is not only a fundamental error but also the basis for attachment, clinging and the development of our numerous prejudices. According to the theory of emptiness, any belief in an objective reality grounded in the assumption of intrinsic, independent existence is simply untenable. All things and events, whether ‘material’, mental or even abstract concepts like time, are devoid of objective, independent existence.
To intrinsically possess such independent existence would imply that all things and events are somehow complete unto themselves and are therefore entirely self-contained. This would mean that nothing has the capacity to interact with or exert influence on any other phenomena. But we know that there is cause and effect – turn a key in a car, the starter motor turns the engine over, spark plugs ignite and fuel begins to burn… Yet in a universe of self-contained, inherently existing things, these events could never occur! So effectively, the notion of intrinsic existence is incompatible with causation; this is because causation implies contingency and dependence, while anything that inherently existed would be immutable and self-enclosed. In the theory of emptiness, everything is argued as merely being composed of dependently related events; of continuously interacting phenomena with no fixed, immutable essence, which are themselves in dynamic and constantly changing relations. Thus, things and events are 'empty' in that they can never possess any immutable essence, intrinsic reality or absolute ‘being’ that affords independence.
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