Source: kushAgra-aniketaH
Hemacandra (10th century) in Siddha-Hema-Śabdanuśāsana, defines Prakrit’s “nature” to be Sanskrit:
“prakṛtiḥ saṃskṛtam, tatrabhavaṃ tata āgataṃ vā prākṛtaṃ” [Sanskrit is the prakṛti and Prakrit is called thus because it originates from Sanskrit]
Another prākṛt grammarian, Mārkaṇḍeya, writes in his grammar Prākṛtasarvasva:
“prakṛtiḥ saṃskṛtaṃ, tatrabhavaṃ prākṛtam ucyate“ [Sanskrit is called the prakṛti, and from there Prakrit originates].
Dhanika, in his ‘Daśarūpakāvaloka’ commentary on Daśarūpaka (one of the most important treatises explaining the 10 types of Indian Drama), says:
“prakṛter āgataṃ prākṛtam, prakṛtiḥ saṃskṛtam” [from the prakṛti comes Prakrit, and that prakṛti is Sanskrit]
Siṃhadevagaṇin while commenting on Vāgbhaṭālaṅkāra writes:
“prakṛteḥ saṃskrtād āgataṃ prākṛtam” [from Sanskrit (which is the Prakṛti) - comes Prakrit]
The Prākṛtacandrikā (a grammar of Prākṛt) says:
“prakṛtiḥ saṃskṛtaṃ, tatrabhavatvāt prākṛtaṃ smṛtam” [Sanskrit is the prakṛti, it is remembered that Prakrit originates from that (prakṛti)]
The Prākṛtaśabdapradīpikā of Narasiṃha says:
“prakṛteḥ saṃskṛtāyāstu vikṛtiḥ prākṛtī matā” [Alterations/changes (vikṛti) of the original Sanskrit - is known as Prakrit]
The Ṣaḍbhāṣācandrikā of Lakṣmīdhara repeats the same statement as the above:
“prakṛteḥ saṃskṛtāyāstu vikṛtiḥ prākṛtī matā” [Alterations/changes (vikṛti) of the original Sanskrit is known as Prākṛt]
Vāsudeva, in his Prākṛtasaṃjīvanī commentary on Rājaśekhara’s Karpūramañjarī says:
“prākṛtasya tu sarvameva saṃskṛtaṃ yoniḥ” [Sanskrit is the mother of all Prākṛt]
Nārāyaṇa, in his Rasika-sarvasva commentary on the Gītāgovindam of Jayadeva, says:
“saṃskṛtāt prākṛtam iṣṭaṃ tato ‘pabhraṃśabhāṣaṇam” [From Sanskrit is derived proper prākṛt, and from that is derived the corrupt-speech i.e. apabhraṃśa]
Śaṅkara, in his Rasacandrikā commentary on the Abhijñānaśākuntala play states (Ref. provided by Dr. Surendramohan Mishra):
“saṃskṛtāt prākṛtam śreṣṭhaṃ tato ‘pabhraṃśabhāṣaṇam” [From Sanskrit is derived best prākṛt, and from that is derived apabhraṃśa]