As time moved forward and the ages changed, the people of the world began to experience the hardships brought by dualities—pleasure and pain, heat and cold, hunger and thirst. The wish-fulfilling trees and the abundant honey of earlier times had vanished, and so, pressed by necessity, people started to consider new ways to sustain themselves. During the Tretā Yuga, these people, troubled by disputes and the pangs of thirst and hunger, found that a new means of livelihood appeared. Rain began to fall as desired, and from this rain, streams and other waters sprang forth, nourishing the land. The continuous rainfall gave rise to flowing streams and rivers, which brought life to the earth each time the rains returned. As the raindrops mingled with the soil, their union produced medicinal plants. From this divine interaction, fourteen kinds of trees and shrubs—some wild, some domestic, some seasonal, and some flowering or fruit-bearing—came into being. These various trees and herbs provided sustenance, and in this way, living beings survived in the Tretā Yuga. Yet, as time passed, passion and greed inevitably arose among the people, a destined influence of the age. Driven by these desires, they began to seize rivers, fields, mountains, trees, shrubs, and medicinal herbs by force, each according to their own strength. As a result, the fourteen types of medicinal herbs perished, retreating into the earth itself. In this way, the Oṣadhyaḥ—the essence of medicinal plants—became one with Pitāmaha, the Grandfather of all beings. Then, with great effort, Pitāmaha milked the earth for the benefit of all creatures, and from that time onward, medicinal herbs were drawn forth only by ploughing the land. Seeking sustenance, people turned diligently to agriculture, which became known as their primary means of livelihood. If not for this change at the end of the Tretā age, those plants would not have survived. Instead, new kinds of plants arose—some water-born, some cultivated by hand. But even then, people, overcome by anger and the power of the age, seized from one another—taking sons, wives, and wealth by force. To restore order and protect the people from harm, the Lord born from the lotus—Brahmā—created the Kṣatriyas, the warrior class, to establish boundaries and defend against injustice. He established the order of varṇa and āśrama by his own power, shaping society through conduct and livelihood according to the universal Self. It was in this age, too, that the practice of sacrifice began, gradually taking shape. Some virtuous souls refrained from animal sacrifice, and then Viṣṇu, all-seeing, performed sacrifice by force. The twice-born praised this act, and from that time, the practice of sacrifice became non-violent. As the Dvāpara age arrived, differences of opinion arose among people. Livelihood was attained only with difficulty, through mind, action, and speech. Bodily hardships increased, and with them came greed, wages, trade, war, and uncertainty about what was true. The branches of the Veda multiplied, dharmas became confused, and the order of varṇa and āśrama was disturbed. Desire and hatred grew alongside these changes. In the Dvāpara age, passion, greed, and intoxication became widespread. Vyāsa, seeing the decline in people’s lifespans and capacities, divided the single Veda into four parts, a process that continued in the ages that followed. In the Tretā age, the one Veda had four divisions, but as lifespans shortened further, Vyāsa divided the Veda even more in the Dvāpara age. With each generation, the sons of seers introduced further divisions, based on differences in perception, arrangement of mantras and Brāhmaṇas, and variations in tones and letters. The wise compiled the collections of Ṛk, Yajus, and Sāman, establishing both general and altered versions according to their seers. Brāhmaṇas, Kalpasūtras, and expositions on mantras were followed by some, while others adhered to earlier traditions. The Itihāsas and Purāṇas, too, were divided with the passage of time: Brāhma, Pādma, Vaiṣṇava, Śaiva, Bhāgavata, Bhaviṣya, Nārada, Mārkaṇḍeya, Āgneya, Brahmavaivarta, Laiṅga, Vārāha, Vāmana, Kūrma, Mātsya, Gāruḍa, Skānda, and Brahmāṇḍa, each with their own divisions and forms. The Laiṅga Purāṇa itself was divided into eleven forms in the Dvāpara age: Manu, Tri, Viṣṇu, Hārīta, Yājñavalkya, Uśanas, Aṅgiras, Yama, Āpastamba, Saṃvarta, Kātyāyana, Bṛhaspati, Parāśara, Vyāsa, Śaṅkha, Likhita, Dakṣa, Gautama, Śātātapa, and Vasiṣṭha, along with many others. With these changes, drought, death, disease, and other afflictions also arose. From the suffering caused by speech, mind, and actions, people experienced disillusionment, which led them to inquire into the nature of liberation from suffering. From such inquiry, detachment arose; from detachment came the perception of faults in worldly existence; and from perceiving these faults, knowledge emerged in the Dvāpara age. Thus, the conduct of the Dvāpara age became characterized by passion and darkness. In the first age, Kṛta, righteousness prevailed; in Tretā, righteousness was still strong; in Dvāpara, it became disturbed; and in the Kali age, it would be all but destroyed. In the Kali age, particularly during the times called Tiṣya and Māyāmasū, and in the slaying of ascetics, people—whose senses were clouded by darkness—committed such acts. Heedlessness, disease, constant hunger and fear, and the dreadful threat of drought and disorder plagued the lands. The authority of scripture faded, unrighteous conduct grew rampant, and the unrighteous became unrestrained, quick to anger, and lacking in understanding. Greed led people to speak falsehoods. In Tiṣya, wicked offspring were born, marked by evil deeds, poor learning, bad conduct, and improper approaches. Thus, over the ages, the world changed—from the purity of Kṛta to the decline of Kali—each age marked by its own challenges, transformations, and lessons for all beings.