vana{dhūmenenḍana---}vikāravat sāmarthyād rātrau bhuṅkta ityetad vyatirekavākyam api gamayati, natu sākṣād iti pratipādayannāha dvitīyetyādi /
Through implication, like [inferring] the modification of fuel [from smoke], it also conveys the contrary statement "he eats at night," but not directly – thus [the author] explains by saying "dvitīya" etc.