Chapter 1: How to Understand the Characteristics of the Truth of Suffering

Original Text: If one delights in pursuing the path beyond the world, one should rely on the state of the Four Noble Truths and gradually generate seven types of mental application. These are, initially, the mental application of discerning characteristics, and finally, the mental application of the fruition of consummate practice, until the attainment of the Arhat fruit. Practitioners of yoga, having briefly studied and extensively analyzed the Four Noble Truths through the supreme teachings, hearing and upholding them, either have already skillfully cultivated mental application or have attained the fundamental meditative absorptions of the form realm and formless realm.

Explanation: If a practitioner delights in directing their mind toward the path beyond the world, they should rely on the state of the Four Noble Truths and gradually generate seven types of mental application. These seven types of mental application are: initially, the mental application of discerning characteristics; followed by the mental application of conviction, the mental application of distancing, the mental application of delighting in renunciation, the mental application of observation, the mental application of consummate practice; and finally, the mental application of the fruition of consummate practice, until the attainment of the Arhat fruit. Practitioners of yoga, having briefly studied and extensively analyzed the principles of the Four Noble Truths through the supreme teachings, hearing and upholding them, either have already skillfully cultivated mental application according to the principles or have attained the fundamental meditative absorptions of the four dhyānas and eight samādhis, even reaching the formless realm.

This passage broadly reveals the content and sequence, or process, of cultivation from an ordinary person to a fourth-stage Arhat. Sentient beings who wish to be liberated from worldly suffering and attain the bliss of Nirvāṇa must cultivate the Four Noble Truths. In the process of cultivating the Four Noble Truths, they must generate seven types of mental application. Mental application refers to attention, focus, and mental engagement—the direction the mind takes. It also refers to contemplation and observation. Different mental applications lead to different directions and thus different results. Only when the mental application of the fruition of consummate practice is generated is the ultimate fruit attained, realizing the Arhat fruit, achieving liberation, and transcending the world.

Original Text: Through four aspects, one understands the characteristics of the Truth of Suffering: the aspect of impermanence, the aspect of suffering, the aspect of emptiness, and the aspect of selflessness. Through four aspects, one understands the characteristics of the Truth of the Origin: the aspect of cause, the aspect of accumulation, the aspect of arising, and the aspect of condition. Through four aspects, one understands the characteristics of the Truth of Cessation: the aspect of cessation, the aspect of tranquility, the aspect of excellence, and the aspect of liberation. Through four aspects, one understands the characteristics of the Truth of the Path: the aspect of the path, the aspect of thusness, the aspect of practice, and the aspect of transcendence. These are collectively called the mental application of discerning characteristics.

Explanation: Cultivating the Four Noble Truths, one understands the characteristics of the Truth of Suffering through four aspects: the aspect of impermanence, the aspect of suffering, the aspect of emptiness, and the aspect of selflessness; one understands the characteristics of the Truth of the Origin through four aspects: the aspect of cause, the aspect of accumulation, the aspect of arising, and the aspect of condition; one understands the characteristics of the Truth of Cessation through four aspects: the aspect of cessation, the aspect of tranquility, the aspect of excellence, and the aspect of liberation; one understands the characteristics of the Truth of the Path through four aspects: the aspect of the path, the aspect of thusness, the aspect of practice, and the aspect of transcendence. These methods together are called the mental application of discerning characteristics.

This passage introduces the general content of cultivating the Four Noble Truths. The cultivation of each truth includes four aspects, making sixteen aspects in total, known as the sixteen aspects of the Four Truths.

Original Text: By ten aspects, one contemplates the Truth of Suffering, thereby penetrating the four aspects of the Truth of Suffering. What are the ten? 1. The aspect of alteration. 2. The aspect of destruction. 3. The aspect of separation. 4. The aspect of intrinsic nature. 5. The aspect of aggregation. 6. The aspect of bondage. 7. The aspect of undesirability. 8. The aspect of insecurity. 9. The aspect of non-acquisition. 10. The aspect of non-mastery. These ten aspects, based on the principle of valid cognition, can be correctly contemplated.

Explanation: By contemplating the Truth of Suffering through ten aspects, one can penetrate the four aspects of the Truth of Suffering. What are the ten aspects? First, the aspect of alteration; second, the aspect of destruction; third, the aspect of separation; fourth, the aspect of intrinsic nature; fifth, the aspect of aggregation; sixth, the aspect of bondage; seventh, the aspect of undesirability; eighth, the aspect of insecurity; ninth, the aspect of non-acquisition; tenth, the aspect of non-mastery. These ten aspects, relying on the principle of valid cognition, can be correctly observed.

This passage introduces ten aspects for contemplating the Truth of Suffering. Only by contemplating the Truth of Suffering through these ten aspects can one penetrate the four aspects of the Truth of Suffering and ultimately realize the Truth of Suffering.

Original Text: Here, based on the principle of scriptural authority, as the Bhagavān said: "All conditioned phenomena are impermanent." Moreover, these conditioned phenomena are briefly of two kinds: 1. The sentient world. 2. The inanimate world. The Bhagavān, regarding the sentient world, stated thus: "Monks, you should know that with the purified divine eye surpassing that of humans, I observe sentient beings at the time of death and birth," extensively explained up to "after the body perishes, they will be reborn in the heavenly world among the fortunate destinies." Through this method, the Bhagavān reveals that with the purified divine eye, He directly perceives that the entire sentient world is of an impermanent nature.

Explanation: Contemplating the Truth of Suffering relies on the principle of scriptural authority taught by the Bhagavān, such as the principle of the impermanence of all conditioned phenomena. The impermanence of all conditioned phenomena is suffering; contemplating the impermanence of all conditioned phenomena is contemplating the Truth of Suffering and the Truth of the Origin. The "conditioned phenomena" mentioned by the Buddha are briefly of two kinds: the sentient world and the inanimate (non-sentient) world. The Buddha said: "With the purified divine eye surpassing that of humans, I observe sentient beings at the time of death and birth," extensively explained up to "after the body perishes, they will be reborn in the heavenly world among the fortunate destinies." This method reveals that the Bhagavān, with His purified divine eye, directly perceives that the entire sentient world is of an impermanent nature.

Beginning from this passage, the Bhagavān specifically expounds on the impermanence of all conditioned phenomena. "Conditioned phenomena" refer to phenomena that have the characteristics of arising, abiding, changing, and ceasing. Anything that arises, abides, changes, and ceases is a conditioned phenomenon; all such phenomena are called "all conditioned phenomena," and they are all impermanent because they exhibit the phenomena of arising, abiding, changing, and ceasing. The Bhagavān perceives all these phenomena with His purified divine eye. Whatever phenomena the Buddha perceives—all phenomena of the world and beyond—are directly perceived; there is no inferential reasoning or false conjecture, because His wisdom is utterly perfect. Sentient beings perceive phenomena through three means: direct perception, inference, and false perception, but the Buddha perceives solely through direct perception, unlike sentient beings. The impermanence of the inanimate world can be studied in the Agama Sutras, such as the Sutra on the Arising of the World, which describes the arising, abiding, changing, and ceasing of the inanimate world.

Original Text: Moreover, the Bhagavān said: "Monks, you should know that this inanimate world remains stable for a long time. After that period, gradually, up to the appearance of seven suns, as extensively described in the Sutra of the Seven Suns, all the earth, mountains, great oceans, Mount Sumeru the great king of mountains, and even the inanimate worlds up to the Brahma realm will be consumed by fire. After the conflagration subsides, not even ashes remain; not even a trace can be found." Through this method, the Bhagavān reveals that the entire inanimate world is of an impermanent nature. Thus, relying solely on the principle of scriptural authority, practitioners, due to the power of their purified faith and mental application, attain certainty regarding the impermanent nature of all conditioned phenomena. Having attained certainty, they repeatedly reflect and contemplate, directly perceiving that all [conditioned phenomena] are impermanent, without contradiction, not relying on external conditions.

Explanation: The Bhagavān stated in the Sutra on the Arising of the World: "Monks, you should know that this Sahā world, the inanimate world, remains stable for a long time now. After that period, gradually, two suns, three suns, and finally seven suns will appear, as described in the Sutra of the Seven Suns. At that time, all the earth, mountains, and great oceans within this inanimate world, as well as Mount Sumeru in the desire realm heavens and even all inanimate worlds of the form realm, will be completely burned. After the conflagration, not even ashes remain; not even any trace can be found."

The events described by the Bhagavān precisely reveal the impermanent nature of all inanimate worlds. Hearing the Bhagavān's exposition and relying on the principle of scriptural authority He taught, practitioners cultivating contemplation strengthen their purified faith in the impermanence of all conditioned phenomena, and their mental application directed toward impermanence becomes more powerful. Thus, they attain certainty regarding the impermanent nature of all conditioned phenomena. Having attained certainty in mind, they further rely on this power of purified faith and mental application to repeatedly reflect and contemplate the impermanent nature of conditioned phenomena, directly perceiving the impermanence of all conditioned phenomena, which accords with the principle of scriptural authority without contradiction. This direct perception does not arise from other causes but from genuine contemplation, perceived by one's own mind.

Contemplating the impermanence of all conditioned phenomena requires reliance on the power of purified faith—faith in the Bhagavān's teaching that all conditioned phenomena are impermanent, maintaining a pure mind without other thoughts. Due to purified faith, one can apply mental application to observe and investigate the impermanent nature. Without purified faith—without believing that all conditioned phenomena are impermanent—one will not apply mental application to observe. Observation is direct perception by one's own mind; if it is not direct perception, it is not called present observation. Direct perception by one's own mind is also called direct experiential observation or direct realization. "Direct" means presently existing, truly existing—not something conceived, imagined, or fabricated by thought. Practitioners, through studying the Bhagavān's scriptural authority on the impermanence of all conditioned phenomena, contemplate the impermanent nature in meditation. When conditions mature, they directly perceive that conditioned phenomena are indeed impermanent, thereby experientially realizing the Truth of Suffering. Because they directly perceive that conditioned phenomena are suffering, they become unwilling to suffer further, and the aspiration to extinguish suffering arises.

Original Text: How does one repeatedly reflect and contemplate the impermanent nature? First, establish two types of phenomena: internal and external. "Internal phenomena" refer to the six sense bases, etc. "External phenomena" are of sixteen kinds. 1. Earth phenomena: cities, towns, villages, houses, marketplaces, etc. 2. Garden phenomena: medicinal herbs, groves, forests, etc. 3. Mountain phenomena: various mountains, arranged differently. 4. Water phenomena: rivers, canals, lakes, streams, ponds, marshes. 5. Activity phenomena. 6. Storehouse phenomena. 7. Food phenomena. 8. Drink phenomena. 9. Vehicle phenomena. 10. Clothing phenomena. 11. Ornament phenomena. 12. Dance, song, and music phenomena. 13. Perfume, garland, and adornment phenomena. 14. Livelihood phenomena. 15. Light phenomena. 16. Male and female service phenomena. These are called the sixteen kinds of phenomena.

Explanation: How does one repeatedly reflect and contemplate the impermanent nature of all conditioned phenomena? First, establish the internal and external phenomena of the five aggregates. Internal phenomena refer to the six sense bases: eye, ear, nose, tongue, body, and mind, etc. External phenomena are sixteen kinds related to food, clothing, shelter, livelihood, and transportation: First, earth phenomena, including cities, towns, villages, houses, marketplaces, etc.; second, garden phenomena, including places where medicine, flowers, plants, and trees are cultivated; third, mountain phenomena, including large mountains, hills, etc., mountains of different sizes; fourth, water phenomena, including rivers, seas, lakes, ponds, etc., places where water gathers; fifth, activity phenomena; sixth, storehouse phenomena; seventh, food phenomena; eighth, drink phenomena; ninth, vehicle phenomena; tenth, clothing phenomena; eleventh, ornament phenomena; twelfth, dance, song, and music phenomena; thirteenth, perfume, flowers, garlands, and adornment phenomena; fourteenth, livelihood phenomena; fifteenth, illumination phenomena; sixteenth, male and female service phenomena.

These phenomena are all impermanent phenomena of the mundane world. They are impermanent because they are conditioned phenomena produced through action, characterized by arising, abiding, changing, and ceasing. After arising, they do not remain for even a moment but continuously change until destruction. Sentient beings engage in these impermanent activities from childhood to adulthood yet do not perceive their impermanence. After studying the scriptural authority on impermanence, the conscious mind easily understands the impermanent nature of these phenomena, but the mental faculty (manas) is dull and reluctant to accept it. Therefore, one must cultivate precepts, meditation, and wisdom, contemplate in meditation, and ultimately realize the impermanent nature. Realization means direct perception—directly observing the impermanent nature of phenomena, not relying on conscious thought or understanding. The impermanent nature clearly presents itself, compelling belief; immediate acceptance is realization, accompanied by samādhi, where the mind abides in the perception of the impermanence of phenomena without wavering.

Original Text: Having established these internal and external phenomena, then, due to the power of mental application directed toward direct perception, one reflects and contemplates the impermanent nature through the aspect of alteration. Here, internal phenomena have fifteen kinds of alterations and eight kinds of causes for alteration. What are the fifteen kinds of alterations of internal phenomena? 1. Alteration due to stages of life. 2. Alteration due to apparent color. 3. Alteration due to shape. 4. Alteration due to prosperity and decline. 5. Alteration due to completeness or incompleteness of limbs. 6. Alteration due to exertion. 7. Alteration due to harm by others. 8. Alteration due to cold and heat. 9. Alteration due to deportment. 10. Alteration due to contact. 11. Alteration due to defilement.

Explanation: Having established these internal and external phenomena, then, to directly perceive these phenomena, one strengthens the power of mental application directed toward seeing the Dharma, and from the perspective of the alteration of phenomena, reflects and contemplates the impermanent nature of internal and external phenomena. Among them, internal phenomena have fifteen kinds of alterations and eight kinds of causes for alteration. What are the fifteen kinds of alterations of internal phenomena? First, alterations due to different stages of life; second, alterations in apparent color, such as changes in skin color like black, white, red, yellow, etc.; third, alterations in shape, such as height, shortness, fatness, thinness, etc.; fourth, alterations in the prosperity and decline of the body, such as having strength or lacking strength, etc.; fifth, alterations in the limbs, such as missing arms, legs, or other disabilities;

Sixth, alterations due to labor, such as being tired or not tired, etc.; seventh, alterations due to harm by others, such as being bullied, falsely accused, slandered, harmed in reputation, etc.; eighth, alterations due to cold and heat, such as fever, chills, etc.; ninth, alterations in deportment and movement, such as bodily laziness, hunched back, difficulty moving, etc.; tenth, alterations due to contact with objects, such as changes in people, things, or situations encountered; eleventh, alterations due to actions performed with a defiled mind, such as changes in wholesome or unwholesome karma; twelfth, alterations due to illness in the body, such as being healthy before but now experiencing sickness and suffering, etc.; thirteenth, alterations due to death, the end of life; fourteenth, alterations after death where the body becomes blue, swollen, and bloated; fifteenth, alterations after death where the corpse disappears, and even the ashes leave no trace.

Original Text: What are the eight kinds of causes for alteration? 1. Accumulation over time and storage. 2. Harm by others. 3. Diminishment through use. 4. Change of season. 5. Burning by fire. 6. Erosion by water. 7. Drying by wind. 8. Encounter with different conditions.

"Accumulation over time and storage" means that although material phenomena are placed and guarded in a good location, after a long time, they naturally deteriorate, their color fades, and alteration can be observed. "Harm by others" means that when various material phenomena are struck or harmed by others in various ways, their shape immediately changes in various ways. "Diminishment through use" means that various colored objects belonging to different owners diminish and alter due to the force of the user's repeated use.

Explanation: What are the eight kinds of causes for alteration? First, accumulation over time and storage; second, harm by others; third, diminishment through use; fourth, change of season; fifth, burning by fire; sixth, erosion by water; seventh, drying by wind; eighth, encounter with different conditions.

"Accumulation over time and storage" means that for phenomena with material form, although they may be placed and guarded in a suitable location, after a long time, they will naturally decay, and their form will show signs of fading and alteration. "Harm by others" means that various material phenomena, when struck by others in various ways or harmed in various manners, will exhibit various alterations in their shape. "Diminishment through use" means that various colored objects belonging to different users, due to the force of the user's repeated use, show signs of wear and alteration.

Original Text: "Change of season" means that in autumn and winter, the flowers, leaves, fruits, etc., of groves and medicinal herbs wither, turn yellow, and fall. In spring and summer, branches, leaves, flowers, and fruits become green, lush, and abundant. "Burning by fire" means that when a great fire rages, it burns villages, towns, cities, and royal capitals, reducing them to ashes. "Erosion by water" means that when a great flood spreads, it washes away villages, towns, cities, and royal capitals, submerging them completely. "Drying by wind" means that when a great wind blows, it dries wet clothes, damp land, crops, and groves, making them increasingly parched and withered.

Explanation: "Change of season" means that in autumn and winter, the flowers, leaves, and fruits of groves, medicinal herbs, etc., wither, turn yellow, and fall. In spring and summer, branches, leaves, flowers, and fruits of groves and medicinal herbs begin to grow again, becoming green, lush, and abundant. "Burning by fire" means that when a great fire breaks out, it burns villages and settlements, reducing cities and royal palaces to ashes. "Erosion by water" means that when a great flood spreads, it submerges villages and settlements, and cities and royal palaces are engulfed by the floodwaters. "Drying by wind" means that when a great wind blows, wet clothes, damp land, crops, and groves are dried by the wind, becoming increasingly parched and withered.

Original Text: "Encounter with different conditions" means that when encountering a contact condition for pleasant feeling, while experiencing pleasant feeling, one encounters a contact condition for painful feeling. When encountering a contact condition for painful feeling, while experiencing painful feeling, one encounters a contact condition for pleasant feeling. When encountering a contact condition for neutral feeling, while experiencing neutral feeling, one encounters a contact condition for pleasant feeling or painful feeling. Furthermore, one with greed encounters conditions for hatred; when the bondage of greed ceases, the bondage of hatred arises. Similarly, one with hatred or delusion encounters conditions for the arising of different types of afflictions. Likewise, when eye consciousness is presently active, it encounters objects of sound, smell, taste, touch, etc. These are called the eight kinds of causes for alteration. All alterations of material and immaterial phenomena arise solely from these eight causes. Beyond this, there are no others, neither exceeding nor additional.

Explanation: "Encounter with different conditions" means that when conditioned by a contact for pleasant feeling, at a time when one should experience pleasant feeling, one instead encounters a contact for painful feeling; when conditioned by a contact for painful feeling, at a time when one should experience painful feeling, one instead encounters a contact for pleasant feeling; when conditioned by a contact for neutral feeling, at a time when one should experience neutral feeling, one instead encounters a contact for pleasant feeling or painful feeling. Additionally, a greedy person encounters conditions for hatred; when the afflictive bondage of greed ceases here, the afflictive bondage of hatred arises there. Similarly, a person with hatred or delusion encounters conditions for the arising of non-hatred or non-delusion afflictions, which is also like this. Likewise, when eye consciousness is presently active, it encounters objects of sound, smell, taste, and touch. These are the eight kinds of causes for alteration. All alterations of material phenomena and immaterial phenomena arise solely from these eight causes. Beyond this, there are no other causes.

Here, "different" means change. When the encountered conditions change, the cause changes, and the result also changes. Causes and conditions for alteration are broadly divided into these eight kinds; further subdivisions may be numerous. Because conditions can change, phenomena are impermanent; because results can change, phenomena are also impermanent. The alteration of causes and conditions can fully and sufficiently demonstrate impermanence.

Original Text: How does one reflect on the impermanent nature of alterations due to stages of life in internal phenomena? By observing oneself or others, from the stage of youth to old age, the continuous succession of conditioned phenomena shows differences before and after, mutually dissimilar. Having seen this, one thinks: "Such conditioned phenomena are impermanent in nature. Why? Because alterations in these internal stages before and after are presently observable."

Explanation: How does one contemplate the impermanent nature of alterations due to stages of life in the body? By observing oneself or others from the stage of youth to old age, the continuous alteration of conditioned phenomena, the differences in phenomena before and after, with no similarities. Having observed these phenomena, one should have this thought: "These conditioned phenomena are truly impermanent in nature." Why does one reach this conclusion? Because within the internal stages of the body, from youth to old age, the changes and differences before and after are indeed presently observable.

Original Text: How does one reflect on the impermanent nature of alterations due to apparent color in internal phenomena? By observing that oneself or others previously had beautiful skin, fresh and lustrous, but later saw deteriorated skin, withered and dry, and then again later saw beautiful skin, fresh and lustrous. Having seen this, one thinks: "Such conditioned phenomena are impermanent in nature. Why? Because alterations in this internal apparent color before and after are presently observable."

Explanation: How does one contemplate the impermanent nature of alterations in the apparent color perceived by eye consciousness in internal phenomena? Observing that oneself or others originally had beautiful skin color, fresh and lustrous, but later found the skin color deteriorated, withered, no longer fresh and lustrous. After some time, one again sees the color beautiful and the skin lustrous. Having observed these phenomena, one thinks: "Such conditioned phenomena are indeed impermanent in nature." Why is this said? Because the apparent color within the body differs before and after, altered and impermanent, presently observable.

Original Text: How does one reflect on the impermanent nature of alterations due to shape in internal phenomena? As with apparent color, so with shape regarding fatness and thinness; it should be understood similarly. How does one reflect on the impermanent nature of alterations due to prosperity and decline in internal phenomena? By observing that oneself or others previously had flourishing family, wealth, and status, seeing all prosperous, but later saw all declined and diminished, and then again later saw prosperity. Having seen this, one thinks: "Such conditioned phenomena are impermanent in nature. Why? Because alterations of prosperity and decline are presently observable."

Explanation: How does one contemplate the impermanent nature of alterations in shape in internal phenomena? Just as with the observed apparent color, alterations in shape regarding fatness and thinness follow the same principle. How does one contemplate the impermanent nature of alterations due to prosperity and decline in internal phenomena? Observing that oneself or others previously had flourishing family, wealth, and status, sometimes seeing them all prosperous, but later seeing them all declined and diminished, and then again later seeing prosperity. Having observed these phenomena, one has this thought: "Such conditioned phenomena are indeed impermanent in nature." Why? Because the alterations of prosperity and decline in family, wealth, and dependents are presently observable.

Original Text: How does one reflect on the impermanent nature of alterations due to limbs in internal phenomena? By observing that oneself or others previously had limbs without deficiency, but later saw limbs deficient, whether done by a king, a thief, a person, or a non-human. Having seen this, one thinks: "Such conditioned phenomena are impermanent in nature." The rest is as previously stated.

Explanation: How does one contemplate the impermanent nature of alterations in the limbs in internal phenomena? Seeing that the limbs of oneself or others were not deficient before, but later seeing the limbs deficient, whether caused by a king's punishment, robbery by bandits, harm by others, or harm by non-humans. Having observed these phenomena, one has this thought: "Such conditioned phenomena are indeed impermanent in nature."

Original Text: How does one reflect on the impermanent nature of alterations due to exertion in internal phenomena? By observing the nature of bodily fatigue, extreme bodily exhaustion in oneself or others, whether caused by running, jumping, leaping, horse riding, or performing various swift bodily actions, and then at another time seeing them free from fatigue and exhaustion. Having seen this, one thinks: "Such conditioned phenomena are impermanent in nature." The rest is as previously stated.

Explanation: How does one contemplate the impermanent nature of alterations due to bodily exertion in internal phenomena? Observing the nature of bodily fatigue, extreme bodily exhaustion in oneself or others, whether caused by fast walking, jumping, repeated leaping, horse riding, or performing various swift bodily actions, and then later seeing that this extreme fatigue is gone, disappeared. When observing these phenomena, one has this thought: "Such conditioned phenomena are indeed impermanent in nature."

Original Text: How does one reflect on the impermanent nature of alterations due to harm by others in internal phenomena? By observing that oneself or others were harmed by others, their bodies altered, whether damaged by knives, sticks, whips, leather straps, spears, lances, etc., or harmed by various poisonous bites of mosquitoes, gadflies, snakes, scorpions, etc., and then at another time seeing no alteration. Having seen this, one thinks: "Such conditioned phenomena are impermanent in nature." The rest is as previously stated.

Explanation: How does one contemplate the impermanent nature of alterations due to harm by others in internal phenomena? By observing that oneself or others were harmed by others, their bodies altered, whether damaged by knives, sticks, whipping, strong ropes, spears, arrows, etc., or poisoned by various mosquitoes, gadflies, snakes, scorpions, etc., but later seeing the body recovered, without alteration. Having observed these phenomena, one thinks: "Such conditioned phenomena are indeed impermanent in nature."

Original Text: How does one reflect on the impermanent nature of alterations due to cold and heat in internal phenomena? By observing that oneself or others, during extreme cold, were uncomfortable, curled up, shivering, bound by cold, longing for warmth; during extreme heat, were comfortable, body stretched, mouth dry, sweating profusely like rain, bound by heat and thirst, longing for coolness; and then later, during cold times, seeing again the previously described states. Having seen this, one thinks: "Such conditioned phenomena are impermanent in nature." The rest is as previously stated.

Explanation: How does one contemplate the impermanent nature of alterations due to cold and heat in internal phenomena? By observing that oneself or others, during extreme cold, were very uncomfortable, curled up, shivering, cold penetrating the body, longing for warm sunlight. Or observing that during extreme heat, the body stretched out, whole body hot and dry, mouth parched. Sweating profusely like rain, hot and thirsty, longing for coolness. Later, during cold seasons, again seeing the phenomena and states described earlier. Having observed these phenomena, one thinks: "Such conditioned phenomena are indeed impermanent in nature."

Original Text: How does one reflect on the impermanent nature of alterations due to deportment in internal phenomena? By observing that oneself or others, in walking, standing, sitting, or lying down, with any deportment, sometimes diminished, sometimes increased. Having seen this, one thinks: "Such conditioned phenomena are impermanent in nature." The rest is as previously stated.

Explanation: How does one contemplate the impermanent nature of alterations in the four deportments in internal phenomena? By observing that oneself or others, while walking, standing, sitting, or lying down, with any deportment, sometimes diminished, sometimes increased. Having observed these phenomena, one has this thought: "Such conditioned phenomena are indeed impermanent in nature."

Original Text: How does one reflect on the impermanent nature of alterations due to contact in internal phenomena? When encountering a contact conducive to pleasant feeling, experiencing pleasant feeling arising from contact with a pleasant object, one naturally discerns the state of pleasant feeling. Just as one discerns the state of pleasant feeling, so one discerns the state of painful feeling and the state of neutral feeling. Due to discerning the alteration of these feelings before and after, they are ever-new, not as before, increasing or decreasing, temporarily existing, suddenly present, then immediately changing and perishing. Knowing this, one thinks: "Such conditioned phenomena are impermanent in nature."

Explanation: How does one contemplate the impermanent nature of alterations due to contact in internal phenomena? When encountering a contact conducive to pleasant feeling, experiencing pleasant feeling arising from contact with a pleasant object, one naturally discerns the state of pleasant feeling. Just as one discerns the state of pleasant feeling, one discerns the state of painful feeling similarly, and discerns the state of neutral feeling likewise. Due to discerning the alteration of these three feelings before and after, the feelings continuously renew and change, not remaining as they were initially. The three feelings sometimes increase, sometimes decrease; various feelings exist only temporarily, suddenly present, soon changing and ceasing. Having observed these phenomena, one has this thought: "Such conditioned phenomena are indeed impermanent in nature."

Original Text: How does one observe the impermanent nature of alterations due to defilement in internal phenomena? One can know previously arisen minds: sometimes with greed, sometimes without greed; sometimes with hatred, sometimes without hatred; sometimes with delusion, sometimes without delusion. One can also know minds defiled by any one of the various secondary afflictions. One can also know minds not defiled by any one of the various secondary afflictions. One can also know that the continuum of that mind, due to afflictions and secondary afflictions, enters states of alteration and non-alteration before and after. Having seen this, one thinks: "Such conditioned phenomena are impermanent in nature. Why? Because alterations due to defilement are presently observable."

Explanation: How does one observe the impermanent nature of alterations due to defilement in internal phenomena? One can know previously arisen defiled minds: sometimes with greed, sometimes without greed; sometimes with hatred, sometimes without hatred; sometimes with delusion, sometimes without delusion. One can also know minds defiled by each type of secondary affliction, and minds not defiled by each type of secondary affliction. One can also know that the continuum of the defiled mind, due to afflictions and secondary afflictions, sequentially enters states of alteration and non-alteration before and after. Having observed these phenomena, one gives rise to this thought: "Such conditioned phenomena are indeed impermanent in nature." Why? Because alterations arising from defilement are presently observable.

Original Text: How does one observe the impermanent nature of alterations due to illness in internal phenomena? By observing that oneself or others previously had no illness, were comfortable and strong, but later saw oneself or others afflicted by severe illness, suffering intensely, encountering sharp bodily suffering as previously described, and then at another time saw again no illness, comfortable and strong. Having seen this, one thinks: "Such conditioned phenomena are impermanent in nature."

Explanation: How does one observe the impermanent nature of alterations due to illness in internal phenomena? By observing that oneself or others previously had no illness, were physically and mentally comfortable and strong, but later saw oneself or others afflicted by severe illness, suffering intensely, and then later saw oneself or others again without illness, physically and mentally comfortable and strong. Having observed these phenomena, one has this thought: "Such conditioned phenomena are indeed impermanent in nature."

Original Text: How does one observe the impermanent nature of alterations due to death in internal phenomena? By observing that presently alive, abiding and supported, but at another time seeing death, only a corpse remaining, empty of consciousness. Having seen this, one thinks: "Such conditioned phenomena are impermanent in nature." How does one observe the impermanent nature of alterations due to lividity, etc., in internal phenomena? By observing that after death, a corpse at one time reaches the livid stage, at another time the putrefying stage, and so on up to the skeletal stage. Having seen this, one thinks: "Such conditioned phenomena are impermanent in nature."

Explanation: How does one observe the impermanent nature of alterations due to death in internal phenomena? Observing that others were alive, abiding peacefully in the world, but later finding them dead, only a corpse remaining, without consciousness. Having observed this phenomenon, one thinks: "Such conditioned phenomena are indeed impermanent in nature." How does one observe the impermanent nature of alterations in the stages of lividity, etc., in internal phenomena? Observing a dead corpse, at one time showing lividity and swelling, at another time the corpse showing swelling and decay, finally leaving only a pile of bones. Having observed these phenomena, one gives rise to this thought: "Such conditioned phenomena are indeed impermanent in nature."

Original Text: How does one observe the impermanent nature of complete disappearance and destruction due to alteration in internal phenomena? By observing that at another time, even this skeletal stage also disappears, completely ruined, scattered, disintegrated, ground to dust, utterly gone, no longer seen by the eye in any form. Having seen this, one thinks: "Such conditioned phenomena are impermanent in nature. Why? Because such forms repeatedly change, with alterations before and after presently observable."

Explanation: How does one observe the impermanent nature of complete disappearance and destruction manifested in internal phenomena? Observing that the remaining pile of bones in the body later also disappears, completely ruined, scattered, disintegrated, every kind of material form no longer visible to the eye. Having observed these phenomena, one thinks: "Such conditioned phenomena are indeed impermanent in nature." Why is this said? Because the form of the corpse after death continuously undergoes transformation, and the phenomena of alteration before and after can be directly observed.

Original Text: Thus, solely by the power of mental application directed toward direct perception, one observes the various alterations and impermanent nature of the fifteen kinds of internal phenomena. Having observed this, one further observes the various alterations and impermanent nature of the sixteen external phenomena. How does one observe the impermanent nature of alterations in earth phenomena? By observing that in this location, previously unbuilt with places for practice, temples, houses, marketplaces, city walls, etc., later seeing newly built, well-constructed and well-adorned structures, and then at another time seeing them decayed, ruined, cracked, fallen, dilapidated, collapsed, burned by fire, or washed away by water. Having seen this, one thinks: "Such conditioned phenomena are impermanent in nature. Why? Because the transformation of such forms before and after is presently observable."

Explanation: Thus, by the power of mental application directed toward direct perception, one observes the various alterations and impermanent nature of the fifteen kinds of internal phenomena. After this, one continues to observe the various alterations and impermanent nature of the sixteen kinds of external phenomena. How does one observe the impermanent nature of alterations in earth phenomena? Observing the location of this land, previously unbuilt with places for practice, temples, houses, marketplaces, city walls, etc., later seeing newly constructed buildings in this location, and then later, seeing these buildings become old and demolished, or fallen into ruin and decay, or burned by fire, or washed away by water. Having observed these phenomena, one thinks: "Such conditioned phenomena are indeed impermanent in nature." Why is this said? Because the transformation of their form before and after is presently observable.