yathā pacatītyādau vidhivākye sāmarthyādaudāsīnyavinivṛttir iṣyate tathā dvitīye 'pi naṭīti siddhamatrāpyasya nivartanam / sparṣṭārthaṃ tu nañcatuṣṭayodāharaṇam //
Just as in an injunctive sentence like "he cooks," the exclusion of indifference is understood through implication, similarly in the second [case] with "not a dancer," the exclusion of this [indifference] is established here too. The example of the four negatives is [given] just to make the meaning clear.