Drawing from a long tradition of Indian and Tibetan commentaries on the Heart Sutra I will offer some food for thought on its central passage: "Form is emptiness, emptiness is form. Form is not other than emptiness; emptiness is not other than form." This pithy statement contains much meaning.
All persons and things are dependent upon their causes and upon their parts and
cannot exist independently of them. They are dependent-arisings; consequently
they are empty of inherent existence. Because all phenomena are dependent-arisings,
they have a nature of emptiness.
2) Conversely; as beings and things have no independent or inherent nature, they must rely on other factors. They must be dependent-arisings.
3) The emptiness of forms is not separate from forms. Forms themselves, which are produced and disintegrate due to the presence of conditions, are by their own nature empty of inherent existence.
4) This absence of inherent existence is their final reality; their mode of abiding, their final mode of being.
5) In sum, the production and disintegration, increase and decrease, and so forth of forms are possible because forms are empty of self-powered existence. Phenomena such as forms are said to dawn from within the sphere of the nature of emptiness.
Consequently, the Heart Sutra says, "Form is emptiness; emptiness is form; form is not other than emptiness; emptiness is not other than form." In this way, emptiness and dependent-arising are shown to be in harmony.
In brief, forms are not empty because of emptiness, forms themselves are empty. Emptiness means not that a phenomena is empty of being some other object but that it itself is empty of its own inherent existence. That a form is emptiness means that the final nature of a form is its natural lack of inherent existence; because forms are dependent-arisings, they are empty of an independent self-powered entity. That emptiness is form means that this natural lack of inherent existence -- which is the absence of a self-powered principle -- makes possible the forms which are its sport or which are established from it in dependence upon conditions. Since forms are the bases of emptiness, emptiness is form; forms appear as like reflections of emptiness.
In my own experience
it is easier to understand that because things are dependent-arisings they are
empty of inherent existence than it is to understand that because things are empty,
they must be dependent-arisings. Although intellectually I know the latter very
well, experience on the level of feeling is more difficult. Nowadays I often reflect
on a statement of Nagarjuna's Precious Garland.
A person is not earth, not water,
Not fire, not wind, not space,
Not consciousness, and not all of them.
What person is there other than these?
First he considers whether the physical elements of the body -- earth (hard things), water (fluids), fire (heat), wind (air), and space (the empty spaces such as the gullet) -- could be the self. Next he examines consciousness. Then he considers whether the collection of all of these could be the self. Finally, he rhetorically asks whether the self could be other than these. In none of these ways can the self be found.
Then Nagarjuna does
not immediately draw the conclusion that the self is not real. Rather, right after
that stanza, he says that the self is not nonexistent but is a dependent-arising
which is set up dependent upon those six constituents named above. Then, based
on this face of dependence, he draws the conclusion that the self is not real:
Due to being [set up in dependence upon]
a composite of six constituents,
A person is not real.
Here, "not real" does not just mean that the self cannot be found when sought from among or separate from the six constituents. Nagarjuna is making the point that although the mind realizing the emptiness of inherent existence sees a mere absence, that very mind promotes an understand that the self is a dependent-arising, avoiding both the extreme of holding that the self inherently exists and the extreme of holding that the self does not exist at all.
Like the two sides of the hand, when looked at one way by examining its deeper nature, there is the emptiness of inherent existence, but when looked at from the other side, there is the appearance of the phenomenon itself. They are one entity. Therefore, form is emptiness and emptiness is form.
You have to be able to understand that the import of emptiness is also the meaning of dependent-arising. They are deeply connected. As your insight into emptiness grows clearer, you will see more and more that objects depend on causes and conditions and on their parts, and they bring about pleasure and pain because they do not exist inherently. If you come to feel that everything is useless because it is empty, you are mistaking emptiness for nihilism. Properly understanding emptiness means realizing how we musty rely on cause and effect. The natural and full understanding of emptiness means a profound understand of the union of appearance and emptiness.
The understanding of emptiness is fantastic, is it not? It can serve as an antidote to the misconception of inherent existence, and yet in itself it also assists in greater understand of cause and effect. That is real understanding of emptiness.
It is impossible to explain the import of the realization of emptiness in the context of just hearing or reading an explanation. It is something that has to be worked at over a long period of time together with the practices of morality -- refraining from harm and extending compassion -- and through making supplications to Buddhas, Bodhisattvas, and other teachers for help in overcoming obstacles. We need many positive causes.