The physical world only has matter and energy. Each living being experiences the world through a set of perceptions (saññā) associated with the realm in which they live. Living beings (and their environments) arise through Paṭicca Samuppāda, providing a unique set of ‘saññā‘ for their survival.
March 27, 2026
Mūlapariyāya Sutta – The Root of All Things
1. The “Mūlapariyāya Sutta (MN 1)” embeds one of the critical “previously unheard teachings” of the Buddha, i.e., the critical role of saññā. Mūlapariyāya means ‘the root of all things’ in the world, i.e., the process by which living beings and things in the world come into existence.
- At the end of that sutta, it states ‘Na te bhikkhū bhagavato bhāsitaṁ abhinandunti‘ OR ‘But the bhikkhus were not pleased in the Blessed One’s words (because they did not understand).’
- I provided a summary of the sutta in “Mūlapariyāya Sutta – The Root of All Things.” I realized that not many people understood it. Since then, we have discussed enough material to lead to a better understanding.
- This post begins a series that will help explain that deep sutta. Recent findings from modern science help us understand certain aspects that people in the Buddha’s time did not have access to. They believed Buddha’s worlds based on faith (from other aspects), but now we have this additional evidence from science.
- Before discussing the sutta, let me point out some other related concepts.
Broad Picture for the 31 Realms of the World
2. The Buddha divided the world into three main sub-worlds of kāma loka, rūpa loka, and arupa loka.
- Living beings of the lowest 11 realms in ‘kāma loka‘ experience a multitude of perceptions (saññā), collectively called ‘kāma saññā.’
- At the highest end, living beings in the 4 arupa Brahma realms in ‘arupa loka‘ experience only a single saññā. They only experience rūpa below the suddhāṭṭhaka level, and thus the name ‘arupa.’
- Those Brahmās who live in the 16 rūpa Brahma realms in ‘rūpa loka‘ experience fewer saññā than beings in ‘kāma loka.’
- See “Saññā In Kāma, Rūpa, and Arupa Loka” for details. It discusses the “Saññā Sutta (AN 11.7)” which explains various types of saññā that operate in the three lokās.
- Even in kāma loka, each realm operates with its own set of saññā. For example, humans and animals live in kāma loka, but they operate under different saññās. There are variations even among different animal species.
Life in Each Realm Is Based on a Set of Saññā
3. Saññā is an ‘innate sense’ that is built into all living beings; see “Saññā – What It Really Means.” Because of that, ‘kāma saññā‘ or ‘an innate sense of liking for sensual pleasures’ arises in us who live in kāma loka.
- The mind of any living being in any of the three lokās is forced to focus on a set of saññā that arise automatically. Thus, a living being never experiences the world ‘as it really is’ until coming across the teachings of the Buddha.
- In that sutta, the Buddha explains that one attains Nibbāna when the mind becomes free of all types of ‘lokiya saññā‘ or ‘any saññā associated with the world.’ The types of saññā can be broadly divided among the three lokās: kāma loka, rūpa loka, and arupa loka. See “Saññā In Kāma, Rūpa, and Arupa Loka.“
Type of Saññā in Kāma, Rūpa, and Arupa Loka
4. Kāma loka operates on a set of ‘kāma saññā.’ The main types based on the six sense faculties are rūpa, sadda, gandha, rasa, poṭṭhabba, and dhamma saññā. Some people (especially in the days of the Buddha) were able to overcome those ‘kāma saññā’ and attain jhāna. Upon attaining a jhāna, one’s mind separates from the ‘kāma loka‘ and enters the ‘rūpa loka,’ which is free of the ‘kāma saññā.’
- However, the mind of someone in a jhāna (unless it is an Ariya jhāna) would have ‘jhānic saññā‘ associated with savitakka, savicāra, piti, sukha, and ekaggatā. As one moves up to higher rūpa loka realms, the number of saññā decreases, and so does the associated ‘stress’ or ‘suffering.’ By the fourth jhāna, the four of the ‘jhānic saññā‘ mentioned above have been eliminated, and one only experiences ekaggatā. At this point, one can start cultivating Ākāsānancāyatana saññā associated with the first realm in the higher-lying arupa loka.
- In the ‘arupa loka‘ (four arupa Brahma realms), the mind is focused on only one saññā. For example, in the Ākāsānancāyatana and Viññāṇañcāyatana realms, the mind is focused on the infinite space and the infinite viññāṇa, respectively. These are the ‘arupa loka samāpatti‘ with the least stress! Thus, the least stress (suffering) is experienced in those highest Brahma realms.
Variety of Saññā Decreases from Kāma Loka to Arupa Loka
5. Living beings in kāma loka have the highest number of sense faculties (six). Thus, many types of saññā are associated with sights, sounds, tastes, smells, touches, and memories, as listed in #4 above.
- Therefore, the number of saññā ‘covering a mind’ is decreased as one moves from the kāma loka to the rūpa loka and then to the arupa loka. It is possible to overcome the ‘kāma saññā‘ by abstaining from akusala kamma and sensual pleasures; anariya yogis were able to do that even before the Buddha. They achieved that by living in isolation away from temptations.
- However, in that ‘anariya process,’ one would not be able to eliminate any of the saṁyojana that binds one’s mind to the rebirth process. Even though they could overcome the ‘kāma saññā‘ temporarily, they could not eliminate the ‘kāma rāga saṁyojana‘, which requires comprehension of the Noble Truths.
Anariya Jhāna and Samāpatti Are Fruitless in the Long Run
6. Consider a person who cultivates the highest arupa samāpatti. As a result, they will be reborn in the highest arupa Brahma realm. However, since all ten saṁyojana remain intact, they will be reborn in the human realm when the lifetime in that realm expires. After that, they can also be reborn in an apāya, i.e., the cycle of rebirth will continue.
- That process can be terminated only by comprehending how the mind attaches (taṇhā) to sensory inputs via ‘mind-made saññā.’ See “Taṇhā – Saññā Leading to Mind-Made Vedanā.”
- This is why understanding the role of saññā is critically important!
- Now, let us get back to our discussion on the three lokās: kāma loka, rūpa loka, and arupa loka.
Physical Bodies and Environments in Kāma Loka, Rūpa Loka, and Arupa Loka
7. The ‘bodies’ of living beings and their environments are also vastly different for the kāma loka, rūpa loka, and arupa loka.
- Those in kāma loka possess six senses (five physical senses and the mind), and their environment includes ‘solid matter’ that brings the sensory inputs of taste, smell, and touch. Thus, they have ‘dense bodies’ and their environments consist of ‘solid objects.’
- The arupa Brahmās in arupa loka have only the mind. Thus, they live well above Earth’s surface without even needing air to breathe. They have fine and invisible ‘mental bodies’ made of just a single suddhāṭṭhaka (‘hadaya vatthu‘ or the ‘seat of the mind’). For comparison, a suddhāṭṭhaka is much smaller than an atom in modern science. See Ref. 1.
- Even those Brahmās in the rūpa loka have ‘mental bodies’ made of just a few suddhāṭṭhaka. They can see and hear without having physical eyes or ears. Without a solid body, they don’t need sleep or shelter. Thus, they also lack a ‘physical environment’ with trees, animals, etc. (like arupa Brahmās), and their habitats are also located well above the Earth’s surface. Both types of Brahmās do not need food; their ‘subtle bodies’ are maintained by kammic energy until the end of their lifetimes.
- This is why modern science is unaware of the existence of rūpa and arupa loka. Their instruments are not sensitive enough to detect the ‘subtle bodies’ of rūpa and arupa Brahmās.
Births in Different Realms Are Due to Corresponding Gati
8. Rebirths are according to the gati (character/habits) that lead to them. A new existence (and its environment) is tailored to provide a unique set of ‘saññā‘ to sustain that existence.
- For example, those who cultivate ‘kāma gati‘ (with a liking for sensual pleasures) are reborn in ‘kāma loka.’
- Some humans see the drawbacks of sensual pleasures and cultivate jhāna. They are said to transcend ‘kāma gati‘ and to cultivate better ‘Brahma gati.’ Then, they are reborn as ‘rūpa loka Brahmās‘ according to their new set of ‘Brahma gati.’
- Some of those who cultivate jhānās advance more along that line and attain arupa samāpatti, thus cultivating even better gati of arupa loka Brahmās. They will be reborn in the arupa Brahma loka.
- The 31 realms are discussed in “31 Realms of Existence.”
All Existences Within 31 Realms Are Temporary
9. However, all those existences have finite lifetimes. At the end of those existences, they return to ‘kāma loka‘ and then can be reborn even in the apāyās with much suffering. That describes the rebirth process, where a lifestream moves among the three lokās over and over. That process is terminated only upon attaining Arahanthood, after one comprehends how it is sustained via Paṭicca Samuppāda based on saññā.
- Gati is also a critical concept in Buddha’s teachings. See, for example, “The Law of Attraction, Habits, Character (Gati), and Cravings (Āsavas),“ “Habits, Goals, and Character (Gati),“ and “Gati (Habits/Character) Determine Births – Saṃsappanīya Sutta.”
Physical Bodies and Environment Are According to Gati/Saññā
10. Those humans who cultivate arupa samāpatti are the ones who are reborn in arupa loka realms. They had (temporarily) overcome both ‘kāma saññā‘ and ‘rūpa loka jhāna saññā‘ to reach ‘arupa samāpattis‘ in their previous human lives. Thus, the life in the arupa loka realms are based on a single saññā that they had cultivated.
- Those humans who cultivate jhānās had (temporarily) overcome only ‘kāma saññā.‘ They had done that after realizing the unfruitfulness and dangers of attaching to sensual pleasures with ‘kāma saññā.‘ Another way to say that is, ‘they had overcome kāma gati‘ and will be reborn in the rupa loka. Thus, their bodies and the environment in the rupa loka arise accordingly via Paṭicca Samuppāda. They do not need dense bodies to eat, smell, or touch. And they also don’t need an environment with vegetation, rivers, houses, etc. They can still communicate among themselves without physical bodies; their vision does not require physical eyes, and they can hear without physical ears. The ‘body of a Brahma‘ is similar to a ‘human gandhabba‘; see Ref. 2.
- In contrast, animals and humans craved sensual pleasures, and that is why they are born in kāma loka. One way to say that is they have ‘kāma gati‘ based on ‘kāma saññā.’ To experience tastes, smell, and touch, they require dense bodies. In addition, they require an environment with solid ground, vegetation, rivers, and other ‘physical infrastructure’ that can provide such ‘close-contact sensory experiences’.
Role of Paṭicca Samuppāda
11. What we discussed above is the basis for how living beings and their environments arise through the universal principle of Paṭicca Samuppāda. See “Paṭicca Samuppāda – ‘Pati+ichcha’+’Sama+uppāda’.”
- I hope you can see the critical role of ‘saññā‘ in the rebirth process, which operates through attachment (taṇhā) triggered by saññā. Those in the kāma loka attach with the kāma saññā; those in the rupa loka attach with ‘jhāna saññā,’ and those in the arupa loka attach with ‘arupa samāpatti saññā.’ See “Taṇhā – Saññā Leading to Mind-Made Vedanā.”
- In ‘kāma loka,‘ living beings and their ‘bodies’ and environment arise to automatically provide ‘kāma saññā‘. In Abhidhamma, the first aspect is explained via ‘uppatti bhavaṅga‘ built into the body. It automatically triggers ‘kāma saññā‘ upon receiving sensory input. Thus, attaching to the ‘kāma saññā‘ is automatic. See Ref. 3.
- It takes a concerted effort to overcome that kāma saññā (temporarily) and transcend to the ‘rūpa loka‘ by cultivating jhāna, as can be done by anariya yogis.
- However, those who comprehend the details of how the ‘kāma saññā‘ arises (i.e, the Mūlapariyāya or ‘the root of all things’ in the world; see #1 above) can permanently overcome the ‘kāma saññā‘ to attain the Sotapanna and higher stages of Nibbāna. See Ref. 4.
Understanding Saññā
12. Saññā is a concept that is a little bit tricky to understand. The closest English word is ‘perception.’ See #3 above for useful links.
- Like all other ‘mental entities’ in pañca upādānakkhandha (rūpa, vedanā, saṅkhāra, viññāna), saññā is a subjective entity. Based on a given sensory input, vastly different mental entities (pañca upādānakkhandha) can arise among different living beings; even between two humans, they could differ significantly.
- All five entities of rūpa, vedanā, saññā, saṅkhāra, and viññāna arise in one’s mind upon experiencing an ‘external rūpa.’
- Those other four entities arise based on ‘saññā.’ In other words, pañca upādānakkhandha is triggered by saññā. Another way to state the same: Paṭicca Samuppāda processes are triggered by saññā. This is a critical point to understand.
13. Here is a simple example. When a human smells rotten meat, they smell a foul odor and would not eat it. However, a pig smells it as a pleasing odor, and they like to eat rotten meat. Thus, the ‘same external rūpa‘ gave rise to two very different ‘mind-made rūpa‘ in a human and a pig; the human experienced a ‘disliked rūpa,’ and the pig experienced a ‘liked rūpa.’
- Thus, a different type of rūpa arises in the mind of a pig (tasty and smelling good version) compared to a human (yucky and smelling bad) when seeing the same piece of rotten meat (the external rūpa). Those opposite types of ‘mind-made rūpa’ arose from different saññā generated in the minds of the human and the pig. The ‘piece of rotten meat, in ultimate reality, does not have an odor or taste!
- That is an amazing conclusion, just like the conclusion that ‘colors’ do not exist in the world and are ‘mind-made’ as discussed in “Rūpa Samudaya – A ‘Colorful World’ Is Created by the Mind.” We will discuss that further in upcoming posts.
Rūpa and ‘External Rūpa‘
14. In the above discussion, it is critical to understand the difference between ‘external rūpa‘ and the ‘rūpa‘ that arises in the mind.
- Please make sure you have understood the following posts: “Rūpa, Vedanā, Saññā, Saṅkhāra, Viññāṇa – Mostly Misunderstood,” “Rūpa Samudaya – A ‘Colorful World’ Is Created by the Mind,” and “Rūpa – What It Really Means.”
- That difference between ‘external rūpa‘ and the ‘rūpa‘ that arises in the mind takes place because of the “distorted saññā.” The ‘saññā‘ associated with a given species is tailored according to their gati and to also optimize their survival in the world.
- We will discuss that in detail in upcoming posts. This is the key to understanding the Buddha’s deeper teachings!
References
1. The Origin of Matter – Suddhāṭṭhaka
2. As we know, even a ‘human mental body’ or gandhabba can see and hear without the aid of eyes and ears when it comes out of the physical body. The ‘mental body’ of a human (i.e., gandhabba) can come out of the physical body in Near-Death Experiences, as we discussed in “Near-Death Experiences (NDE): Brain Is Not the Mind.”
3. “Bhava and Bhavaṅga – Simply Explained!” and “State of Mind in the Absence of Citta Vithi – Bhavaṅga.”
4. “Sotapanna Stage via Understanding Perception (Saññā)” with newest posts in “Buddha Dhamma.”