The Element of Space in the Tathāgatagarbha

In the third volume of the Śūraṅgama Sūtra, the World-Honored One taught us: 如来藏中，性觉真空，性空真觉，清静本然，周遍法界。 This means that the nature of space is the nature of the tathāgatagarbha; the element of space and the tathāgatagarbha are neither identical nor different. The element of space pervades the ten directions and the entire dharma realm, and the element of space can generate empty space. The sūtra says: 虚空生汝心内，如片云点泰清里。 Here, "mind" refers to the mind of the tathāgatagarbha. Empty space is born within the mind of the tathāgatagarbha, and within the tathāgatagarbha it occupies only a tiny position, just like the proportion that a cloud occupies within the sky.

In the world where sentient beings live, where does empty space come from? Where do the gaps within material objects come from? Where does the space of our living environment come from? Where do the gaps within cells and within the body all come from? What functions do empty space and various kinds of space have? Whether broad or narrow, all these spaces come into being from non-existence, and all are subject to arising and ceasing. Since they are subject to arising and ceasing, there must be seeds that give birth to these spaces, and only then can space be born. All dharmas are born from the tathāgatagarbha, and space is one of all dharmas, also produced by the tathāgatagarbha; moreover, the tathāgatagarbha can only use the seeds of the element of space to give birth to empty space.

The space born from the tathāgatagarbha includes the empty space and space of the external world, as well as the gaps and spaces within the body. Because there is space in the external world, all material form can be accommodated, matter can move, sound, gases, and scent-objects can propagate, various forms of energy can be transmitted, and sentient beings can survive within empty space. External empty space is formed by the tathāgatagarbhas of all sentient beings jointly outputting the seeds of the element of space, and it is jointly upheld by the tathāgatagarbhas of all sentient beings. Empty space plays an absolutely vital role: the worlds of the ten directions are established and exist within empty space, celestial bodies move through empty space, sentient beings walk, sit, and lie down within empty space, carrying out all kinds of activities of survival, and all kinds of objects exist and operate within empty space.

Various materials also contain gaps and spaces. The differing amounts of these gaps give rise to different structures of matter, resulting in different densities and different properties of matter. The space within matter is also jointly formed and upheld by the tathāgatagarbhas of all sentient beings who share collective karma. The density of a material is precisely the proportion of space within it. When the proportional content of space differs, the structure of the material differs, and its physical properties differ. If the proportions of earth, water, fire, and wind in a material are equal, but the proportion of the element of space differs, then the volume of the material differs, and its density differs.

Take compressed biscuits, for example, which differ from ordinary biscuits: because ordinary biscuits have been compressed, the space within them is reduced, and the moisture has been squeezed out. The proportion of the earth element contained in the biscuit is therefore greater, the density of the biscuit is greater, and eating it makes one feel full more easily and less easily hungry. If a material expands, the content of space increases, the volume grows larger, the density becomes smaller, and the nature and function of the material change. Thus the element of space also plays a very important role within matter.

When space differs, the energy produced by the movement of matter also differs. Take the high jump and the long jump: the length of the run-up space differs. If it is too long or too short, the jumping power is small; when the spatial distance is appropriate, the momentum of the run-up is great, the energy is great, the jumping power is great—that is, the energy is great—and one jumps farther and higher. Take another example: throwing a stone at a wall. When the distance and space from the wall differ, the force with which the stone strikes the wall differs—that is, the momentum and energy differ—and the degree of damage to the wall differs. Therefore space and empty space are extremely important dharmas. When living beings live crowded together, the space is small and they live without ease. For example, in raising chickens, if the space for activity is too small, the chickens will fall ill or even die.

As for space, there is the empty space jointly transformed and created by the tathāgatagarbhas of sentient beings, and there are also the spaces, gaps, and crevices transformed and created by the tathāgatagarbha of each individual sentient being. The spaces and gaps within the body are created by one's own tathāgatagarbha alone using the seeds of the element of space, including the space within cells. Every tissue and structure in the body contains gaps and spaces, generated by the individual sentient being's tathāgatagarbha alone using the seeds of the element of space. Because there is space within the body, food, gases, and blood can flow, and sentient beings can breathe and sustain their lives. Not only is there space within the internal organs; there is space in the bones, muscles, and various bodily fluids as well. Even the smallest cellular tissues in the body contain space, and the various molecular structures within cells also contain gaps. Only thus can molecules, ions, and other tiny particles move, and only then can cells carry out metabolism. Because the content of the element of space within molecules differs, molecular structures differ, properties differ, and the roles they play within the body differ. The four great elements together with the element of space compose the three-realm world of sentient beings, and these five great elements exist everywhere.

Empty space is one of the forms of material form; it is an object of the eye consciousness's direct perception and valid cognition, and it is also one of the conditions for the arising of the eye consciousness and the ear consciousness; it is subject to arising and ceasing. Empty space is not like turtle hair or rabbit horns—something imagined and utterly nonexistent. Something utterly nonexistent cannot be seen by the eye consciousness and cannot be discriminated by it; that would belong purely to the erroneous cognition of the mind consciousness. But empty space is the boundary-aspect of form: the moment the eye consciousness sees it, it immediately knows it is space. Therefore empty space is an existent dharma, produced later, and in the future it will also cease. In the state of nirvāṇa without remainder, there is no kind of space or spatial expanse whatsoever, let alone empty space. Therefore empty space and space are generated by the tathāgatagarbha using the seeds of the element of space, and the seeds of the element of space have the aspect of generative capacity. Thus the element of space among the seven great elements is a seed, capable of generating space, gaps, and empty space, so that sentient beings can survive within empty space and matter can operate within empty space. The world of the five aggregates cannot be separated from empty space, cannot be separated from the element of space, and the element of space has the aspect of generative capacity. Space is the tathāgatagarbha. The element of space pervades the ten directions and the entire dharma realm; it is the nature of the tathāgatagarbha. The Śūraṅgama Sūtra says: 空生大觉中，如海一沤发。 "Space arises" means that empty space is born, born from the great awakened mind, just like a bubble arising in the great ocean, which in the end will also perish; what arises and ceases is illusory. Therefore the empty space born from the tathāgatagarbha has its function: without empty space there would be no existence or operation of any dharma. Yet this function of empty space is an illusory function, subject to arising and ceasing. In the state where the tathāgatagarbha alone exists, not even the slightest crevice exists, let alone empty space. Therefore the element of space is a seed, has the aspect of generative capacity, and can generate all kinds of space; all are the nature of the tathāgatagarbha.