There was once when Buddha was staying at Savatthi, in Jeta's grive, in Anathapindika's park. At that time there was a wanderer called Potthapada who was at the debating hall near the Tinduka tree, in the park of Queen Mallika with a group of 300 wanderers.
Buddha woke up early one day and headed to Savatthi for alms but it was too early so he decided to go to the debating hall instead to see the wanderer Potthapada. Potthapada was sitting with his crowd of wanderers shouting, making a commotion and indulging in various kinds of rowdy discussions on kings, robbers, ministers, armies, wars, luxurious items, women, gossip, speculations, talk on departed, talk of being and non-being and so on.
When Potthapada saw Buddha coming from a distance, he asked his followers to keep quiet because if they are quiet, Buddha may come and visit them. So the wanderers kept absolute silent. Buddha came to the wanderers and Potthapada prepared a seat for him after which he sat down beside him. Buddha asked him what they were talking about before he came. Instead of telling Buddha what they were discussing earlier, Potthapada asked buddha on his views on the higher extinction of consciousness and how they take place.
Question on cessation of consciousness
Potthapada told Buddha that according to some ascetics they believe that "perceptions arise and cease without any cause or condition (Arise by random chance). When they arise one is consciousness; when they cease then one is unconsciousness". But some others said " No, perceptions are a person's self, which comes and goes (a self can be controlled). When it comes, one is conscious; when it goes, one is unconscious." Another said :" No that's not how it is. There are ascetics and brahmins with great powers (magical powers over consciousness of man). They draw down consciousness into a man and withdraw it. When they draw it down into him, he is consciousness but when they withdraw it, he is unconscious." Yet another said: " No that's not how it goes. There are deities with great powers. They draw down consciousness into a man and withdraw it. When they draw it down into him, he is conscious and when they withdraw it, he is unconscious. " So Potthada asked buddha which theory is right and how will buddha explain the higher extinction of consciousness.
Buddha rejected the theory of consciousness comes and passes away without a reason or a cause. Buddha asserts the absoluteness of the law of karma to refute this claim; it is by means of a cause, that consciousness comes and goes (cause and effect). It is by training some forms of consciousness arise and by training some pass away. "And what is that training?" continued the Buddha.
“A Tathágata arises in the world, an Arahant, fully-enlightened Buddha (he has realized the four noble truths and discovered the noble eightfold path by himself) , endowed with wisdom and conduct, Well-Farer, Knower of the worlds (he knows the arising, the cessation and the means to the cessation of the worlds), incomparable Trainer of men to be tamed (he surpasses in terms of virtue, knowledge, concentration, deliverance and understanding), Teacher of Gods and humans, enlightened and blessed. He, having realized it by his own super-knowledge, preaches the Dhamma, which is lovely in it’s beginning, lovely in its middle, lovely in it’s ending, in the spirit and in the letter, and displays the fully-perfected and purified holy life."
This training consists of morality and meditation. A monk who is perfected in moralities (watching his speech, action and thoughts) sees no danger anywhere. He experiences a blameless bliss that comes from maintaining this Ariyan morality.
Training in meditation by guarding his sense doors, he reaches different stages of jhanas. Through this training, some perceptions arise and some pass away.
Form realm Jhanas
In 1st jhana, sensations of lust and unskillful mental qualities disappear. A subtle perception of delight and happiness arises, born of detachment. In 2nd Jhana, with the subsiding of thinking and pondering, the monk gains inner tranquility and unity of mind. The subtle perception of delight and happiness born of detachment vanishes and there arise the perception of delight and happiness born of concentration. In 3rd Jhana, with the fading away of delight he dwells in equanimity, being mindful and clearly aware. The previous sense of delight and happiness born of concentration vanishes and there arises the perception of equanimity and happiness. In 4th Jhana, pleasure and pain is abandoned, previous joy and grief disappear and the monk reaches a state beyond pleasure and pain which is purified by equanimity and mindfulness. The previous sense of equanimity and happiness vanishes, there arises the subtle perception of neither happiness nor unhappiness.
Formless realm jhana
Sphere of infinite space: Transcends beyond perceptions of physical forms, perceptions of resistance disappear, perceptions of diversity not heeded and he perceives infinite space and remains in the sphere of infinite space. Sphere of infinite consciousness: Passing beyond the sphere of infinite space, seeing that consciousness is infinite. He remains in the sphere of infinite consciousness. Sphere of infinite nothingness: transcending beyond the sphere of infinite consciousness, see that there is "no thing", he reaches the sphere of nothingness.
Then Buddha said to Potthapada, when the monk has reached and gained such controlled perception, he progresses from stage to stage and he reaches the limit of perception. He will ponder and think that mental activity is worse for me, lack of the mental activity is better for me. If he were to think and imagine, then the perceptions attained this far will cease and coarser perceptions will arise in him. Then he neither thinks nor imagines. Then these perceptions arise but other coarser perceptions do not arise. He attains cessation of perception through sucessive steps.
Finally he reaches the final stage of sphere of neither perception nor non-perception.
Further questions on perception
Potthapada asked buddha : " is the submit of perception One or Many?" Buddha replied: " I teach it as one and many. The disciple attains successively to the cessation of each perception through progressively steps thus i teach it as one and many. "
Potthapada asked again: " Does perception arise before knowledge or knowledge arise before perception or do both arise spontaneously?" Buddha replied: " Perception arises first then knowledge. With the arising of perception comes knowledge, this is how it is conditioned."
Potthapada then asked: " Is perception a person's self or is it a separate entity? " Buddha through counter questioning showed Potthapada that no matter how he thinks about the self: whether as the physical body (gross self), a mental body (mind-made self), or formless self, perceptions and the self have to be different entities. Perceptions change continuously depends on different conditions unlike the "self".
Questions that Buddha will not answer
Then Potthapada started to ask questions that Buddha will not answer : - Is the world eternal or not eternal ? - Is the world finite or infinite? - Is the soul same as the body? - Does the tathagata exist after death or does he not exist after death?
Buddha did not answer these questions as it is not conducive to the purpose, not conducive to the dhamma , not the way to embark on the holy life, it does not lead to disenchantment, to dispassion, to cessation, to attainment of higher knowledge, to calm, to enlightenment, to nibbana. That's why Buddha had not declare a clear answer to these questions about cosmology, the soul, and the after-death state.
Potthapada then asked if the above was not declared by Buddha, what had Buddha declared instead? Buddha replied that he had declared the four noble truths : This is suffering, this is the origin of suffering, this is the cessation of suffering and this is the path leading to cessation of suffering. The four noble truths is conducive to the purpose, not conducive to the dhamma , is the way to embark on the holy life, it leads to disenchantment, to dispassion, to cessation, to attainment of higher knowledge, to calm, to enlightenment, to nibbana. That's why Buddha had declared the four noble truths. After that, Buddha left the place.
After Buddha left, the rest of the wanderers mocked Potthapada for agreeing with whatever buddha had said. The wanderers said that they do not understand a word Buddha had said and that Buddha did not reply questions on cosmology, self and post-death states. Potthapada replied that he did not understand on the part of whether the world is eternal, whether tathagata exists after death and whether the world is infinite but what ascetic Gotama (Buddha) taught is sound, true and grounded in dhamma so why should he disapprove Buddha's teachings?
Citta's meeting with Buddha
2-3 days later, Citta who is the son of the elephant trainer wet with Potthapada to see Buddha. Citta paid respect to Buddha, Potthapada exchanged courtesies with Buddha before the sat down beside Buddha to discuss about the previous conversation with the wanderers after Buddha left. Buddha mentioned briefly that those wanderers are ignorant and sightless But Potthapada amongst them has some insight. Buddha explained that questions about cosmology (world eternal/finite?), the self, and the post-mortem status of a Tathagata are declared to be “uncertain” because they are not conducive to Nibbana. On the other hand, Buddha taught the Four Noble Truths which are conducive to nibbana.
Then Buddha gave an example of a conversation between himself and other recluses and Brahmins. These ascetics and brahmins believe that 'the self is perfectly happy and healthy after death and free from disease.' I went and asked whether that was their view or not and they acknowledged that it was their view. And I asked them whether - they knew a place in the world that was perfectly happy - have they ever been perfectly happy for a whole night, or for a whole day, or even for half a night or day? - if they know a way or a method by which you can realize a state that is always happy? - if they have ever heard the voices of devas/deities who had realized rebirth in a perfectly happy world But the ascetics and brahmins answered "No" to all the above questions. Hence don't you think Potthapada, that these talk of those recluses and Brahmins turn out to be witless?
Buddha gave another example of how a man long for the most beautiful woman in the land. Then the people around him will ask him - do you know whether she is a noble Khattiya lady, or brahmin rank, or of the trader class, or of artisan class? - do you know what her name is, or her family name - do you know whether she is tall, or short, or of medium height - do you know if she is dark or fair or golden in color - do you know which village, or town, or city she dwells in? The man would have answered No to all the above questions because he is yearning for someone he doesn't know and has never seen before. Hence don't you think Potthapada, that these talk of this man turn out to be witless? Similarly for those ascetics and brahmins who believe that the self after death is entirely happy and free from disease, don't you think that their talk is witless too? Potthapada agreed.
Buddha gave another example: if a man were to build a staircase for a palace at a crossroad. People will ask him which direction the staircase should face, doe he know the height and size of the staircase. He would have to answer: 'No.' Then the people around him will ask why is he making a staircase that he does not know of and has not seen before. So in such a case, Buddha reaffirmed to Potthapada that the talk of the man making a staircase that he has no idea of is actually witless talk. Potthapāda agreed with the Buddha.
Three kinds of self
Buddha then explained to Potthapada the three kinds of self: Acquired self, mind-made acquired self and formless acquired self. He elaborated further :the gross acquired self is made up of 4 elements nourished by material food we eat. The mind-made acquired self is made by the mind, and has form making up of limbs and organs complete and perfect but does not need solid food. The formless acquired self does not have a form and is made up of perception.
Buddha then told Potthapada that : " I teach a doctrine that leads to the abandoning of the defiling mental states about all three of these assumed selves. If you follow this doctrine, these unwholesome mental states will disappear and the states which lead to purification of the mind increase then one realizes and remains in the full perfection and purity of wisdom here and now."
"Potthapāda, you may think even if one's unwholesome mental states disappear and purification and wisdom increase but one might continue to be unhappy. But Potthapāda, that would be an inaccurate judgment and statement because when such conditions are fulfilled, then there will only be joy and happiness, tranquility, continual mindfulness and clear awareness which is a happy state."
"Potthapāda, others might question us thus if the doctrine of abandoning defiling mental states referring to the gross acquired self, mental, mind-made self or formless self ?" Then we should reply 'Why this very one that you see before you is what I mean.' Don't you think, Potthapāda, this talk will then turn out to be well grounded?" Potthapada agreed with Buddha on that.
Citta's Question on the Three Kinds of Self
At this point, Citta, the son of the elephant trainer, said to the Blessed One: "At the time when the gross acquired self is assumed, would if be wrong to assume the co-existence of the mind-made and formless selves? Is the gross acquired self the only self that is real? But if the mind-made self is assumed, then are the other two not real? And if the formless self is assumed, are the other two not real?" In other words, Citta asked Buddha which self is the truly existent one or do the selves all co-exist?
Buddha replied: " Citta, when any one of the three assumed selves is present, then we do not speak of the other two selves. We speak only of the one self that is currently assumed at any one time. (for example when we are talking about the gross acquired self we do not talk about the mind-made self and formless self during that setting).
Buddha used counter question to allow Citta to understand about the three selves. So he asked Citta: if people should ask you: 'Did you exist in the past, or not? Will you exist in the future, or not? Do you exist now, or not?' How would you answer?" Citta replied : " I shall reply that I existed in the past, and did not not exist in the past; I shall exist in the future, and shall not not exist; I do exist now, and I do not not exist."
Buddha asked Citta again if people were to ask him: 'that past self that you had, is that your real self; and the future and present selves unreal? Or the future self that you will have, is that real one; and the past and present ones unreal? Or is the self that you have now the real you; and the past and future ones unreal?' - How would you answer?" Citta replied : "I will say that the past self that I had was real to me at the time when I had it; and the others were unreal. The present self is real to me now; and the others are unreal. In the future, the future self will be real and the others unreal." Buddha then replied that Citta had answered the question on the different selves himself i.e. when any one of the three assumed selves is present, then we do not speak of either of the other two.
Buddha went on : "Just so similarly, Citta, from a cow comes milk, and from the milk comes curds, and from the curds comes butter, and from the butter comes ghee, and from the ghee comes junket. Hence when we speak of milk we do not call it curds, or butter, or junket; and just so the curds or butter or ghee or junket are not called by any of the other names. In the same way, Citta, when any one of the three assumed selves is present, then we do not speak of either of the other two. For these are merely names, expressions, turns of speech, designations in common use in the world. But a Tathāgata [one who has fully realized the truth] makes use of them, but does not misapprehend them."
After hearing this : Potthapāda, the wanderer, said to the Blessed One: "Excellent, Blessed one! Excellent! Just as if one were to turn upright what had been turned upside down, or to reveal what was hidden, or to point out the right path to one who was lost, or to bring a lamp into a dark place so that those with sight could see forms, in the same way, Lord, the Blessed One has expounded the Dhamma in numerous ways. I shall go to the Buddha, to the Dhamma, and to the Sangha for refuge. May the Blessed One accept me as a lay follower gone for refuge from this day onward for as long as I live."
Citta on the other hand also praised Buddha for the excellent dhamma taught to him, seek refuge in the buddha, dhamma and sangha but in addition he asked for ordination by the Buddha. Buddha ordained Citta and the newly ordained venerable Citta who was zealous and earnest went into seclusion and in a short time attained arahantship. Venerable Citta knew that 'Destroyed is birth, the holy life has been lived, what had to be done has been done, there is nothing further beyond this.'
So in summary, this is a discourse given to a wanderer Potthapada. Buddha discussed about the cessation of consciousness, the various jhana states, the concept of perception and the three kinds of self which are gross acquired self, mind-made self and formless self. He advised Potthapada and Citta not to ask questions which will not benefit them on the path to enlightenment as those questions on cosmology and post death states do not bring about wisdom and knowledge. He also told them not to spend so much time discussing on topics which are not beneficial and are witless. Instead Buddha emphasized the understanding and teaching of four noble truths which will be fruitful for the path to liberation,nibanna.
References: 1. www.accesstoinsight.org 2. https://suttacentral.net/ 3. The long discourses of the Buddha (Bhikkhu Bodhi)