Mbh 12.305.1a

"'"Vasishtha said, 'It is thus, in consequence of his Ignorance and his association with others that are invested with Ignorance, that Jiva has recourse to millions and millions of births every one of which has dissolution in the end. In consequence of his transformation into Chit invested with Ignorance, Jiva betakes himself to millions of abodes one of which is liable to end in destruction, among intermediate beings and men and the deities. In consequence of Ignorance, Jiva, like Chandramas, has to wax and wane thousands and thousands of times. This is truly the nature of Jiva when invested with ignorance. Know that Chandramas has in reality full sixteen portions. Only fifteen of these are subject to increase and decrease. The sixteenth (i.e., that portion which remains invisible and which appears on the night of the New-moon) remains constant. After the manner of Chandramas, Jiva too has full sixteen portions. Only fifteen of these, (viz., Prakriti with Chit's reflection, the ten senses of knowledge and action, and the four inner faculties) appear and disappear. The sixteenth (viz., Chit in its purity) is subject to no modification. Invested with Ignorance, Jiva repeatedly and continually takes birth in the fifteen portions named above. With the eternal and immutable portion on Jiva primal essence become united and this union takes place repeatedly. That sixteenth portion is subtile. It should be known as Soma (eternal and immutable). It is never upheld by the senses. On the other hand, the senses are upheld by it. Since those sixteen portions are the cause of the birth of creatures, creatures can never, O monarch, take birth without their aid. They are called Prakriti. The destruction of Jiva's liability to be united with Prakriti is called Emancipation. The Mahat-Soul, which is the twenty-fifth, if it regards that body of sixteen portions called the Unmanifest,[1617] has to assume it repeatedly.