"Yudhishthira said, 'I desire, O thou of Kuru's race, to know what the origin and what the end is of all creatures; what is the nature of their meditation and what are their acts; what are the divisions of time, and what the allotted periods of life in the respective epochs. I desire also to know in full the truth about the genesis and the conduct of the world; the origin of creatures into the world and the manner of their going on. Indeed, whence their creation and destruction? O best of virtuous persons, if thou art minded to favour us, do tell us this about which I ask thee. Having heard before this excellent discourse of Bhrigu unto the regenerate sage Bharadwaja which thou didst recite, my understanding, purged of ignorance, has become exceedingly attached to yoga, and withdrawn from worldly objects rests upon heavenly purity. I ask thee about the subject, therefore, once more. It behoves thee to discourse to me (more elaborately).'
"Bhishma said, 'In this connection I shall recite to thee an old narrative of what the divine Vyasa said unto his son Suka when the latter had questioned the former. Having studied the illimitable Vedas with all their branches and the Upanishads, and desirous of leading a life of Brahmacharya in consequence of his having earned excellence of religious merit, Suka addressed these very questions, about which his doubts had been solved, to his father the island-born Rishi who had removed (by study and contemplation) all doubts connected with the topic of the true import of duties.' "Suka said, 'It behoveth thee to tell me who the Creator is of all beings, as fixed by a knowledge of time, and what the duties are that should be accomplished by a Brahmana.'
"Bhishma said, 'Unto his son who had questioned him, the sire, having a knowledge of both the past and future, conversant with all duties and endued with omniscience, thus discoursed on the subject.'
"Vyasa said, 'Only Brahma, which is without beginning and without end, unborn, blazing with effulgence, above decay, immutable, indestructible, inconceivable, and transcending knowledge, exists before the Creation. The Rishis, measuring time, have named particular portions by particular names. Five and ten winks of the eye make what is called a Kashtha. Thirty Kashthas would make what is called a Kala. Thirty Kalas, with the tenth part of a Kala added, make what is known as a Muhurta. Thirty Muhurtas make up one day and night. Thirty days and nights are called a month, and twelve months are called a year. Persons conversant with mathematical science say that a year is made up of two ayanas (dependent on sun's motion), viz., the northern and the southern. The sun makes the day and the night for the world of man. The night is for the sleep of all living creatures, and the day is for the doing of action. A month of human beings is equal to a day and night of the Pitris. That division (as regards the Pitris) consists in this: the lighted fortnight (of men) is their day which is for the doing of acts; and the dark fortnight is their night for sleep. A year (of human beings) is equal to a day and night of the gods. The division (as regards the gods) consists in this: the half year for which the sun travels from the vernal to the autumnal equinox is the day of the deities, and the half year for which the sun travels from the latter to the former is their night. Computing by the days and nights of human beings about which I have told thee, I shall speak of the day and night of Brahman and his years also. I shall, in their order, tell thee the number of years, that are (thus) for different purposes computed differently in respect of the Krita, the Treta, the Dwapara, and the Kali yugas. Four thousand years (of the deities) is the duration of the first or Krita age. The morning of that epoch consists of four hundred years and its evening is of four hundred years. (The total duration, therefore, of the Krita yuga is four thousand and eight hundred years of the deities). As regards the other yugas, the duration of each gradually decreases by a quarter in respect of both the substantive period with the conjoining portion and the conjoining portion itself. (Thus the duration of the Treta is three thousand years and its morning extends for three hundred years and its evening for three hundred). The duration of the Dwapara also is two thousand years, and its morning extends for two hundred years and its evening also for two hundred. The duration of the Kali yuga is one thousand years,
and its morning extends for one hundred years, and its evening for one hundred. These periods always sustain the never-ending and eternal worlds. They who are conversant with Brahma, O child, regard this as Immutable Brahma. In the Krita age all the duties exists in their entirety, along with Truth. No knowledge or object came to men of that age through unrighteous or forbidden means. In the other yugas, duty, ordained in the Vedas, is seen to gradually decline by a quarter in each. Sinfulness grows in consequence of theft, untruth, and deception. In the Krita age, all persons are free from disease and crowned with success in respect of all their objects, and all live for four hundred years. In the Treta, the period of life decreases by a quarter. It has also been heard by us that, in the succeeding yugas, the words of the Vedas, the periods of life, the blessings (uttered by Brahmanas), and the fruits of Vedic rites, all decrease gradually. The duties set down for the Krita yuga are of one kind. Those for the Treta are otherwise. Those for the Dwapara are different. And those for the Kali are otherwise. This is in accordance with that decline that marks every succeeding yuga. In the Krita, Penance occupies the foremost place. In the Treta, Knowledge is foremost. In the Dwapara, Sacrifice has been said to be the foremost, In the Kali yuga, only Gift is the one thing that has been laid down. The learned say that these twelve thousand years (of the deities) constitute what is called a yuga. A thousand such yugas compose a single day of Brahman. The same is the duration of Brahman's night. With the commencement of Brahman's day the universe begins to start into life. During the period of universal dissolution the Creator sleeps, having recourse to yoga-meditation. When the period of slumber expires, He awakes. That then which is Brahman's day extends for a thousand such yugas. His nights also extends for a thousand similar yugas. They who know this are said to know the day and the night. On the expiry of His night, Brahman, waking up, modifies the indestructible chit by causing it to be overlaid with Avidya. He then causes Consciousness to spring up, whence proceeds Mind which is identical with the Manifest.'"