> Is the cosmos infinite? > The Scales of Buddhist Cosmology > No Known Beginning > Time is Cyclical > Commentarial Developments
『I ain't readin' this whole dang page! 』
Here are the highlights:
1. The Buddha refused to say whether or not the cosmos is infinite.
2. There are four broad realms in which beings may be reborn: hell, the earthly realm, the godly realm, and the Brahmā realm. Finer divisions can be made, but the suttas are not clear about the details.
3. The realms can also be organized into “planes,” according to the types of existence which take place there: there is the sense-desire plane, where beings are primarily driven by sensuality; there is the form plane, where beings exist with subtle material bodies; and finally, there is the formless plane, where beings do not possess any form.
4. The cosmos consists of numerous "world-systems" and "groups of world-systems," all of which share the same cosmological layout of realms which are inhabited by the same sorts of beings. Basically, the Buddhist cosmos is a multiverse.
5. The cosmos undergoes cycles of evolution and devolution, wherein some realms are born and destroyed time and time again. No beginning to this process can be discovered, and no Creator God set this process in motion.
A common debate in the Buddha’s time was whether or not space was finite or infinite - an issue which still has no scientific consensus. This was one of the topics the Buddha included in his list of things he refused to speak about. In fact, he said outright that one who holds any view on the issue is incapable of living the holy life (MN 63).
The reason for this, as with the other “unanswered questions,” seems to be that no answer to this question can bring someone closer to enlightenment. Several suttas (DN 11, SN 2.26, AN 4.45, AN 4.46) feature stories about individuals who sought to find “the end of the world,” where no beings are reborn and suffering doesn’t arise. In each case, the individual learns that no such place can be found. Conjecture about the cosmos (lokacintā) is also included in the list of “unthinkable things” which lead to confusion or madness (AN 4.77), likely another reason the Buddha stayed silent on the topic.
What the suttas do make clear is that the cosmos is absolutely huge.
The Buddha spoke about the cosmos in a way that reveals several different levels of scale - I identify five general levels into which the cosmos may be divided. From smallest to largest, these are: a realm; a plane; a world-system; various groups of world-systems; and the cosmos in a broad, comprehensive sense.
Before explaining these different levels, I want to note that the suttas often use the same word for each of these scales, with context alone being the means of distinguishing which is being discussed. That word is “loka,” which is usually translated as “world.” In some cases, other terms can be used when specificity is especially important, but by and large each of the five categories rest on this one term. Furthermore, “loka” can also be used to discuss the beings within a particular level of the cosmos - “manussaloka,” for example, refers to “the human world” in an abstract sense, since we share a world with inhuman creatures.
The smallest level of the cosmic scale is a “realm.” The Theravāda tradition developed a detailed list of 31 Realms of Rebirth. Since Buddhist cosmology corresponds closely to the idea of rebirth, these realms are usually defined by whatever sorts of beings are reborn there. As such, even in this list, there are not necessarily 31 unique locations; for example, “humans” and “animals” are separate destinations in the list, although they may occupy the same physical spaces. In this way, boundaries between “realms” may either be spatial or conceptual in a more abstract sense.
As useful as the list of 31 realms is, the suttas are more ambiguous. Trying to come up with a clean number of realms or establish a clear map with well-defined boundaries between the more granular levels of the realms is difficult and not worth the effort. Still, the texts demonstrate that there are boundaries between the more broad levels.
Boundaries Between Realms
In DN 11, we see the story of a monk who was able to manifest “a path to the gods” (devayāniya magga) as well as “a path to Brahmā” (brahmayāniya magga). The sutta clearly depicts at least three realms separated by boundaries that can be crossed: the earthly realm, a godly realm, and a Brahmā realm, where even more highly refined gods live. Within the godly realm, the monk visited several different classes of beings, but the sutta itself makes no effort to explain which of these beings exist in their own realms, and which of them share space with one another. In the Brahmā realm, the text describes the “Mahābrahmā” manifesting in the presence of the “Brahmakāyika devas” (gods in the company of a Brahma - in other words, the higher gods) in a way that strongly suggests that the former and the latter may occupy different spaces. At the end of his journey, the monk is described as vanishing from the Brahmā realm (brahmaloka) and reappearing on Earth, in front of the Buddha. This passage makes use of a common pericope found throughout the suttas to describe beings vanishing and reappearing “as easily as a strong person would extend or contract their arm.” This is used to depict the Buddha, advanced monks, and gods alike crossing the boundaries between realms.
MN 97 depicts Sāriputta discussing various states of rebirth with a dying man, and again, we see a similar situation, where some of these states are clearly separated from one another, while other states are described vaguely enough to leave open the possibility of sharing space. Hell (niraya) and the animal-womb (tiracchānayoni) are clearly separate destinations. However, the animal-womb and “humankind” (manussā) obviously share the same space - where does this leave the “ghostly domain” (pettivisaya), which is mentioned in-between rebirth as an animal and as a human?
After discussing human life, Sāriputta discussed various types of gods. Context from other texts informs us that this marks a transition from “this realm” to the “godly realm” (devaloka), but the sutta itself doesn’t explicitly mark this transition. Furthermore, like the previous sutta, this one makes no attempt to draw borders between the different types of gods Sāriputta mentioned. However, Sāriputta finished his conversation by teaching the dying man about the Brahmā-realm (brahmaloka), clearly separating it from the godly realm.
The suttas are clear about this much: there is the hell realm (niraya); there is the earthly realm, including the human world (manussaloka) and the animal kingdom (tiracchānayoni, “animal womb”); there is the godly realm (devaloka); and finally, there is the Brahmā realm (brahmaloka). These broad categories of realms can be divided into smaller “sub-realms,” occupied by different classes of beings, though the exact nature of these finer divisions is often unclear.
Next comes the “plane,” of which there are three: the plane of “sense-desire existence” (kāmabhava), the plane of “form existence” (rūpabhava), and the realm of “formless existence” (arūpabhava). The suttas do not explicitly refer to these planes in the way the later tradition does, using terms such as “kāmaloka” (sense-desire world) or “kāmabhūmi” (sense-desire plane) which emphasize the cosmological nature of these categories, but the suttas discuss them in a way which makes this perfectly reasonable (ex: DN 15).
This scheme organizes the realms of rebirth by way of the natures of the beings who occupy them. The plane of sense-desire is specifically discussed in DN 33, which explains that the beings who occupy these realms are “under the sway of sensual pleasures.” This is further broken down into three subcategories: 1) Beings who are under the sway of “presently-arisen sensual desires,” specifically “humans, some gods, and some beings in the underworld.” 2) Beings who are under the sway of sensual pleasures from sense-objects they create themselves, specifically a type of god called “The Gods Who Love to Create” (Nimmānarati). 3) Beings who are under the sway of sensual objects created by others, specifically a type of god called “The Gods Who Control the Creations of Others” (Paranimmitavasavattī).
I don’t believe the other two planes are discussed like this in the suttas; however, from context clues throughout the texts, we can confidently fill in the blanks. The formless plane clearly includes the types of rebirth which correspond to meditative states called “the formless attainments.” The form plane, then, comprises the higher gods - which exist between the lesser “sensual rebirths” and the highest formless rebirths.
Altogether: we have the sense-desire plane, which includes the hell realm, the earthly realm, and the deva realm. Next, we have the form plane, where beings with subtle heavenly bodies exist (sometimes called “luminous forms”), which includes the lesser parts of the Brahmā realm. Finally, we have the formless plane, where beings exist without any material body, neither gross nor subtle, and this includes the higher parts of the Brahmāloka.
Larger than the plane is the “world” (loka) or “world-system” (lokadhātu), which would roughly correspond to our understanding of a solar system, with the caveat that Buddhist cosmology does not neatly correspond to modern astronomy. AN 10:29 tells us that a world-system includes the following: a moon; a sun; a massive mountain called “Mount Sineru” (or Sumeru in Sanskrit) which serves as the “axis mundi” of the Buddhist world; four earthly continents named Jambudīpa, Aparagoyāna, Uttarakuru, and Pubbavideha; four great oceans; Four Great Kings (protector gods who watch over the four quarters); attendants of the Four Great Kings; gods of the 33; Yāma gods; Joyful Gods; Gods Who Love to Create; Gods Who Control the Creations of Others; and a Brahmā realm.
It's strongly implied that the text is referring to the realms of the various classes of gods listed here. This is supported by the fact that the Chinese parallel (MA 215) lists the heavens explicitly, using the Chinese character for "heaven" (天) in the relevant instances. It is interesting to note that the hell realm (niraya) is not included in this list of a world-system’s contents; I have no explanation for this, and won’t present my own speculation here.
Next, there are “groups of world-systems.” It is possible to compare this to the modern idea of the “multiverse,” where multiple instances of “world-systems” span outward into the vast cosmos. (ex: AN 3.80). First, there is the minor group of 1,000 worlds (sahassī cūlanikā lokadhātu). It is described as spanning “1,000 times as far as the moon and sun revolve,” and as containing “1,000 moons, 1,000 suns, 1,000 Mount Sinerus,” etc. In other words, it contains 1,000 different world-systems.
Next, there is the medium group of 1,000,000 worlds (dvisahassī majjhimikā lokadhātu). It is described as extending for 1,000 minor systems of 1,000 worlds. In other words, it contains 1,000,000 different world systems.
Finally, there is the great group of 1,000,000,000 worlds (tisahassī mahāsahassī lokadhātu). It is described as extending for 1,000 medium systems of 1,000,000 worlds. In other words, it contains 1,000,000,000 different world systems.
Space Between the World-Systems
Between the world-systems are expanses of “space between the worlds” (lokantarikā aghā). The suttas describe these spaces as being completely dark, untouched by the light from the suns or moons of any world-system (SN 56.46). There are only four moments when these spaces become illuminated: when someone who will become a Buddha is conceived; then again when they are born; once more when they become enlightened; and finally, when they first reveal the Dhamma. In each instance, a brilliant light appears, reaching even the abysses of space (AN 4.127).
Interestingly, living beings are said to reside in these spaces (DN 14, AN 4.127). The darkness in which they reside is so severe that they aren’t even aware that others live there with them until that light appears - then, for the first time, they realize they aren’t alone. Nothing else is said about these beings, and they aren’t even given a name; the suttas only refer to them as “the sentient beings reborn there (in the spaces between worlds).” The commentaries later fleshed out the descriptions of these beings and declared that these spaces were realms of hell, but this is not found in the suttas.
Finally, there are instances where the term "loka" seems to refer broadly to the cosmos as a whole. At this scale, discussions gesture broadly to the entirety of conditioned existence.
In Buddhist cosmology, the cosmos is understood as a vast body of world-systems. Each of these world-systems shares the same structure, all containing the same types of realms filled with the same types of beings. In this way, we can understand the Buddhist cosmos as a sort of “multiverse” filled with parallel universes. All living beings experience the cycle of rebirth across this complex network of realms and world-systems. Furthermore, there are spaces between the world-systems that are dark and filled with a unique type of living being. The vastness of the cosmos cannot be understated, but the Buddha refused to say whether or not it was infinite.
There are two salient features of the Buddhist conception of time: 1) the cosmos has no discernible beginning, and 2) time is cyclical. Both of these ideas inform one another.
Regarding the first point, the Buddha said “samsāra has no known beginning” (SN 15.1) - samsāra meaning “transmigration,” the process of beings undergoing birth, death, and rebirth time and time again. He taught that “no beginning can be found,” and the unfathomable number of lifetimes we have lived throughout time is supposed to serve as inspiration for us to pursue enlightenment. Thus, we see in the suttas: “For such a long time you have undergone suffering, agony, and disaster, swelling the cemeteries” (ibid). “The flow of tears you’ve shed while roaming and transmigrating is indeed more than the water in the four oceans” (SN 15.3). “The flow of blood you’ve shed when your head was chopped off while roaming and transmigrating is indeed more than the water in the four oceans” (SN 15.13).
Many religions feature an elaborate creation myth, where the universe is crafted by the hand of a Creator, marking the first moment of time. Buddhism subverts this trope in its own version of “the genesis” (found in DN 1, DN 24, and others).
Eventually, the cosmos begins to contract - this involves the destruction of many realms of rebirth. As a result, during this period, beings are mostly reborn as “Ābhassara” (Radiant) Brahmās in the brahmaloka. These beings have “mind-made” bodies (as opposed to bodies born through sexual reproduction) which produce light. They move freely through the air, feeding only on the mental feeling of “rapture” (pīti).
Following this period, the cosmos once more expands, and the other realms of rebirth begin reappearing. An empty “Brahmā Palace” (brahmavimana) manifests. Some Ābhassara being eventually dies, and is reborn in that Brahmā palace. Being the first such being to be reborn below the Ābhassara realm, it exists all alone, and eventually the thought occurs to it: “I wish there were others here with me.”
Completely unrelated to this thought, other Ābhassara beings start dying and being reborn in the company of that first Brahmā. As a result of kamma, the first being enjoys a higher state of birth - it is longer-lived, more beautiful, and more powerful. Being completely ignorant of the cosmic and kammic processes at play, it reaches the conclusion that it must be the Mahābrahmā - the Great Brahmā, the Creator, the highest divinity. “These beings appeared in my presence when I willed them to exist! Surely I am their Maker.” The other beings reach this same conclusion - after all, that great being was there before them, and its power surpasses anything they can imagine.
Buddhism also has its own version of an apocalypse (AN 7.66). It begins with the onset of a long drought, said to last for hundreds of thousands of years; this causes plants to die off, leading to a loss of forests, foods, and medicines. A second sun eventually appears in the sky, drying up small rivers and lakes. Great rivers, too, disappear with the appearance of a third sun. A fourth sun takes away the great lakes. The ocean begins to dry up with the appearance of a fifth sun, leaving little pools of seawater which only reach one’s ankles. A sixth sun appears, causing earth and Mount Sineru both to smoke and smolder. With the seventh and final sun, the smoldering erupts into a terrible fire. Earth and Mount Sineru both are destroyed without a trace, and wind blows the flames as high as the Brahmaloka.
In both instances, it’s worth pointing out that the Buddha used these ideas to convey important messages. The first story is clearly a means of ridiculing the worship of the Brahminical god, Mahābrahmā, as the creator. The second story was used to emphasize the importance of understanding impermanence. However, I think it’s unwise to reduce these aspects of Buddhist cosmology to mere metaphors used as teaching aides. The details we see in them are never at odds with the rest of Buddhist doctrine, and cross-referencing these passages with others found throughout the canon reveals a level of consistency which suggests that these stories are not strictly symbolic.
Here, it is necessary to remind ourselves of the second point - time is cyclical. These Buddhist versions of the “genesis” and “apocalypse” are situated in the framework of the kappa, often translated as “aeon.” I like to call this a “cosmic cycle.” The suttas present four stages to a cosmic cycle (AN 4.156):
1) the period where the cosmos contracts
2) the period where the cosmos remains contracted
3) the period where the cosmos expands, and
4) the period where the cosmos remains unfolded.
The fourth period is the one in which we presently exist.
The first in this list, the period of contraction, is the ending of one cosmic cycle. This is when beings are mostly born in the Ābhassara Brahmā realm, presumably because the lower realms are being destroyed by the cataclysm of the seven suns. The period of expansion, then, marks the beginning of another world-cycle, when beings begin to be reborn in other realms once again, beginning with the Mahābrahmā being who first appears in the newly-manifested Brahmā Palace.
This is a pattern which occurs time and time again, and as I mentioned above, there is no beginning to this process which can be discovered. As far back as anyone could possibly imagine, the cosmos has evolved and devolved, expanded and contracted, and realms have been born and destroyed - all the while, we have lived and died in an unfathomable number of lifetimes.
Even a kappa itself cannot be measured. The Buddha refused to put a number to the cosmic cycle, or even to any of its four periods. After describing each period, the Buddha said “it is difficult to count how many years, hundreds of years, thousands of years, or hundreds of thousands of years this takes” (AN 4.156). Instead, the length of a kappa is conveyed through powerful imagery. We are asked to picture a massive mountain, and imagine that once every century, someone comes and gently wipes a small part of the mountain one time with a soft cloth. This entire mountain would erode away as a result from the cloth wipe’s friction before one kappa had passed (SN 15.5).
As the Buddhist tradition developed, cosmological ideas were elaborated and expanded by monastic commentators - sometimes in ways that contradict the suttas. Let's briefly look at some of these developments as found in the Theravada tradition.
The ambiguity of the term "loka" seems to have been a concern for the monastic community, because they introduced new terms to discuss the various parts of the cosmos more explicitly. For example, two terms emerged to refer to the "loka" as a world-system: there is "okasaloka," or "world-in-space," and "cakkavala," which means something like "circular enclosure." The latter term appears in three places in the Nikayas, but each instance is clearly a late interpolation. We find it in a poetic verse at the end of the Mahāparinibbāna Sutta (DN 16). The commentary says outright that this was added by Sri Lankan elders. It is also found in the Buddhavamsa and the Apadāna, two hagiographical texts in the Khuddaka Nikāya. These texts are among the latest entries in the Pali Canon. The word was almost certainly unknown to the earliest Buddhist community.
The commentaries introduced many details regarding the structure of the cakkavāla. In the Visuddhimagga ("The Path to Purification," a detailed manual expanding fine doctrinal points written by Buddhaghosa), exact measurements are given for a cakkavāla's diameter and circumference, as well as the heights of its constituent geographical features. Those features themselves are greatly elaborated upon as well. The "axis mundi" of Mount Sineru is now surrounded by seven rings of jeweled mountain ranges, each descending in height. Water separates each of the rings, and beyond the seventh lies the Great Outer Ocean. The four earthly islands each gain 500 smaller islands. At the edge of the cakkavala, there is a final ring of mountains called the cakkavālapabbata (cakkavāla mountain), also called the cakkavālasiluccaya (cakkavāla rock - Sn-a 3:7) and cakkavālamukhavatti (cakkavāla edge - Dhp-a 3:7). This final range acts as the edge of the world-system, leaving us with a neatly-contained cosmological body. All of this exists on a great body of caustic water (lokasandhārakaudake), which itself rests on a body of vapor or air (nabhamugga). Cakkavālas exist side-by side, described like wheels ("wheel" being another meaning of the word "cakka) placed together and touching one another (DN-a 14), with the empty gap between any three world-systems being the "space between worlds" (lokantarikā aghā) discussed earlier.
This idea of the space between worlds was also greatly extrapolated. This area, characterized by its profound darkness, becomes the "Lokantara Niraya," the "Hell Between Worlds." The beings previously alluded to in the suttas are now presented as massive, blind bat-like creatures who hang by their claws from the outside of the world's-edge mountain range. They crawl about in cold, desolate darkness, and on occasion, one will bump into another. Unaware of the existence of any other living creature, they believe they have found something to eat, and scramble in an attempt to consume one another. This causes them to fall into the caustic waters upon which the world-system rests, where they dissolve and die (DN-a 14, MN-a 2).
Later innovations go beyond mere extrapolation - they directly contradict what we find in the suttas. While the Buddha refused to discuss the possible infinitude of the cosmos, even declaring such discussion as completely antithetical to the spiritual path, later sources state quite bluntly that there are an infinite number of cakkavalas, as seen in the Manorathapurani (the commentary to the Anguttara Nikaya) and the Visuddhimagga.
 The information in this section comes from:
“The Buddhist Conception of the Universe” by K. N. Jayatilleke, and
"The Buddhist Cosmos: A Comprehensive Survey of the Early Buddhist Worldview" by Punnadhammo Mahathero