How the Buddha Described the Chance of Rebirth in the Human Realm

Revised May 5, 2017, February 29, 2020; re-written June 7, 2021

Living a Moral Life Is Not Enough

1. Many people believe that if we live a “good, moral life,” a human rebirth or rebirth in higher deva worlds is guaranteed. That is a misconception. Even if we do not accumulate a single new bad kamma in this life, we may have accumulated many bad kamma in past lives. That is why it isn’t easy to get a human existence (bhava). 

  • Evidence for rebirth is at “Evidence for Rebirth.” Rebirth can occur not only as a human but in any of the 31 realms. Most suffering in the cycle of rebirth occurs in the lowest four realms: niraya (hell), asura, animal, and peta realms. Of those four, only the animal realm is visible to us. They are collectively called the apāyās.
  • Getting a “human existence (bhava)” is rare. But once one grasps human bhava, one could be born (jāti) many times as a human until the kammic energy for that human bhava is exhausted. That is why children can recall past lives. In between consecutive human births, that lifestream exists in the nether world or “para lōka” as a gandhabba with a subtle body; see “Hidden World of the Gandhabba: Netherworld (Para Lōka).”
  • The 31 realms of existence are described in “The Grand Unified Theory of Dhamma.”
Most Rebirths Are in the Four Lowest Realms

2. Starting with the “Nakhasikhā Sutta (56.51)” there are about 80 suttās in the Saṁyutta Nikāya 56 that describe the chance of rebirths in good realms (human and above) compared to those in the lowest 4 realms. 

  • Here is the English translation at Sutta Central: “A Fingernail (SN 56.51)“. You can read the whole series there. 
  • Those suttās specifically state the rarity of rebirth in a “good realm” and the common occurrence of rebirths in undesired realms. Many suttās state specifically that for a sentient being in any realm, rebirths will be mostly in the niraya (hell), animal (tiracchāna), and hungry-ghost (peta) realms; see SN 56.102 through SN 56. 131. 
  • Another version of the Nakhasikhā Sutta is in Saṁyutta Nikāya 20, summarized below.
  • Before that, it is good to emphasize the difference between a human bhava and births with a human body (jāti) within that human bhava.
Human Bhava Is Rare – But It Can Last a Long Time

3. Some people ask the following question: If human birth is so rare, why do rebirth accounts indicate human rebirth only after a few years of death? The answer lies in the fact that it is a human bhava that is rare.

  • When a sentient being is born a human, that “human bhava” has a specific kammic energy, say several thousand years worth. In that case, the person may be born (jāti) many times with a human body. In between, that human lives with only a manomaya kāya (i.e., as a gandhabba.)
  • For example, if a Deva dies and gets human bhava, then at the cuti-paṭisandhi moment, a human gandhabba is born into human bhava. After some time, that gandhabba enters a womb, and a human baby is born. When that human grows old and dies, there is still much more time left in the human bhava. Thus, the gandhabba emerges from that dead body and waits for another womb. See “Bhava and Jāti – States of Existence and Births Therein” and “Cuti-Patisandhi – An Abhidhamma Description.”
  • In most other realms (i.e., Deva, Brahma), there is only one jāti within that bhava. Multiple jāti within a bhava is common in the human and animal realms.
  • It isn’t easy to get a human bhava, but once in a human bhava, one can be born tens or even hundreds of times as a human. A given animal may be reborn thousands or even millions of times in that animal realm to exhaust that kammic energy.
  • Of course, we cannot see realms other than the human and animal. We can easily discern the rarity of human bhava by comparing the number of humans to the number of animals. While there are only about 8 billion humans, there are multiple trillions of ants alone! However, modern science has shown that billions of microscopic sentient beings live in a single human body. Let us discuss that next.
The abundance of Animal Life Compared to Human Life

4. Even though the similes in the suttās below may seem out of proportion with the realities, it is not. Modern science has given a boost to Buddha Dhamma by making many things clear. Ordinary humans were unaware of the existence of innumerable microscopic living beings until the invention of the microscope in the 1500s. In  1676, Van Leeuwenhoek reported the discovery of microorganisms. He observed numerous tiny living beings in a glass of water; see https://en.wikipedia.org/wiki/Microscope

Here is a short video showing countless such microscopic creatures:

  • If you go out and dig some dirt, millions of living organisms can be found there. There may be a few humans in a household, but possibly billions or even trillions of microscopic living beings. The oceans cover two-thirds of the Earth’s surface, and the living creatures there are much more densely packed. And there are beings in other 29 realms that we cannot see. Seven billion humans are a thumb-full compared to countless living creatures associated with the Earth (as the Buddha stated in the Nakhasikha Sutta; see below).
  • Uncountable sentient beings are living in the water. One can actually “see” such microscopic beings in a glass of water if one develops abhiññā powers; see “Power of the Human Mind – introduction.” One time, a bhikkhu who had developed abhiññā skills but had not become an Arahant saw the presence of a large number of microscopic beings in a glass of water. He tried to filter them out but was unsuccessful and became distraught. The Buddha told him that “it is not possible to live in this world without harming other beings. It is necessary to live this life to attain Nibbāna” and to drink the water. The INTENTION there is to quench the thirst; see “How to Evaluate Weights of Different Kamma.”
  • Modern science has confirmed that millions of living beings are on a single human body (and any other large animal). Scientists have used sophisticated instruments to see such microscopic creatures. See, “There are as Many Creatures on your Body as there are People on Earth!“.
  • Now, let us briefly discuss a few of the suttās mentioned in #2 above.
1. From the Nakhasikha Sutta (SN 20.2):

Pāli Version: Nakhasikha Sutta (SN 20.2)

Translation:

At Sāvatthī. Then the Buddha, picking up some sand on his fingernail, addressed the bhikkhus: “What do you think, bhikkhus? Which is more: the little bit of sand on my fingernail or this great Earth?”

Bhante, the great earth is far more. The little bit of sand on your fingernail is tiny. Compared to the great Earth, those cannot be compared or even imagined; it is not even a significant fraction.”

“In the same way, bhikkhus, sentient beings reborn as humans, are few as this bit of sand on my fingernail. But those not reborn as humans are many as the sand on this great Earth. Therefore, you should strive diligently and without delay to end this suffering in the rebirth process”.

2. Dutiyachiggaḷayuga Sutta (SN 56.48)

Pāli Version: Dutiyachiggaḷayuga Sutta (SN 56.48)

Translation:

Bhikkhus, suppose that this great Earth had become one mass of water, and a man would throw a yoke with a single hole upon it. An easterly stream would move it eastward. A westerly stream would move it westward; a northerly flow would move it northward. A southerly stream would move it southward.

There was a blind turtle that would come to the surface once every hundred years. What do you think, bhikkhus, would that blind turtle, coming to the surface once every hundred years, insert its neck into that yoke with a single hole?”

“It would be a rare occurrence, Bhante, that the blind turtle, coming to the surface once every hundred years, would insert its neck into that yoke with a single hole.”

“So too, bhikkhus, how extremely rare that one is born a human.

You have this rare chance now, bhikkhus, to be not only born a human but be born while a Tathāgata has arisen. While the Dhamma and Discipline proclaimed by the Tathāgata shines in the world.

Therefore, bhikkhus, you should strive without delay to understand the following. ‘This is suffering (dukkha). This is the cause of suffering (dukkha samudaya). This is how that cause can be removed (dukkha nirōdhaya). And this is the way leading to the cessation of suffering (dukkha nirōdha gāmini patipadā).’”

3. Assu Sutta (SN 15.3)

Pāli Version and translations at Assu Sutta (SN 15.3)

Translation:

First, the Buddha made the famous statement: “Anamataggoyam bhikkhave, samsarō pubbā kōti na pannāyati avijjā nivārananam sattānam taṇhā-samyōjananam sandhāvatam samsāratam.

  • Translated:Bhikkhus, this rebirth process has no discernible (na pannāyati) beginning. Beings whose minds are covered by ignorance and are bound to this rebirth process with bonds of craving.

The rest of the sutta is as follows:

“What do you think, bhikkhus: Which is greater, the tears you have shed while trapped in this rebirth process or the water in the four great oceans? (crying because of being born into a bad birth or being separated from loved ones in good births).”

“As we understand the Dhamma taught to us by the Bhante, the tears we have shed while trapped in this beginning-less rebirth process is greater than the waters in the four great oceans.”

“Excellent, bhikkhus. It is good that you thus understand the Dhamma taught by me. That is the larger: the tears you have shed while trapped in this beginning-less rebirth process — not the water in the four vast oceans.

Long have you (repeatedly) experienced the death of a mother. The tears you have shed over the death of a mother while trapped in this beginning-less rebirth process are greater than the water in the four vast oceans.

Long have you (repeatedly) experienced the death of a father, death of a brother, death of a sister, death of a son, death of a daughter, loss of relatives, or loss of wealth. The tears you have shed over diseases while trapped in this beginning-less rebirth process would fill the four vast oceans.

Why is that? The beginning of this rebirth process is not discernible.”

  • There are 20 suttas in Saṁyutta Nikāya 15 (SN 15.1 through SN 15. 20) that provide various analogies to describe the length of the rebirth process. In another analogy, the blood from uncountable times when one is killed while born as a specific animal (deer or cow, for example) is more than the water in the four oceans.
Summary

1. The Buddha used many analogies to describe how long the rebirth process is: infinite. There is no discernible beginning to “sentient life.” The principle of Causality dictates that there can be no “beginning.” Infinity is hard to comprehend. Scientists have only recently realized this; see “Infinity – How Big Is It?” and  “The Infinity Problem in Buddhism.”

2. The other suttās discussed above emphasized that being born a human, Deva, or Brahma, is extremely rare. Therefore, each of us has spent MOST of that time in the suffering-filled lowest four realms (apāyās.) Even though the realms at and above the human realms have much less suffering than the apāyās, the time spent in those higher realms would have been insignificant.

3. Thus, each of us (and any sentient being living today) would have lived miserable lives MOST OF THAT TIME in the “beginningless” rebirth process.

4. That is the suffering addressed in the First Noble Truth (the truth about suffering or “dukkha sacca” pronounced “sachcha.”) The Second Noble Truth is about the causes of that suffering (the truth about “dukkha samudaya.”) The Third Noble Truth says that suffering can be stopped by eliminating those causes (the truth about “dukkha nirodhaya.”). The Fourth Noble Truth is how to achieve that goal (the truth about “dukkha nirodha gāmini patipadā.”)

Next, “Kamma, Debt, and Meditation“……….