purāṇaṃ mānavo dharmaḥ sāṅgo vedaścikitsitam / ājñāsiddhāni catvāri na hantavyāni hetubhiḥ //
"The Purāṇa, the Law of Manu, the Veda with its auxiliary [sciences], and medicine – these four are [to be considered] self-sufficient commandments and should not be attacked with reasonings."