Mimamsasutra 99.2

99.2

ācāryavacanaṃ hi bhavati pūrvapakṣe - sarvāsu tithiṣv amāvāsyeti. saṃnihitaṃ ca śāstram - paurṇamāsyāṃ paurṇamāsyā yajeta, amāvāsyāyām amāvasyayā yajed iti. tena śrutiviruddhavacanān na satyavācaḥ, tasmād apramāṇam.

For the teacher's statement in the prima facie view is: "The new-moon sacrifice may be performed on all lunar days." But there is an adjacent scripture: "One should sacrifice on the full-moon day with the full-moon sacrifice, and on the new-moon day with the new-moon sacrifice." Hence, because their statements contradict direct scriptural statement, they are not truthful persons; therefore, it is not an authoritative means of knowledge.