Udayana, the author of Atmatattva-viveka was a Maithila brahmana by birth and flourished in the second half of the tenth century. Besides his celebrated work Atmatattvaviveka, he wrote Laksanamala. Nyayakusumarijali, Nyayaparisuddhi and Kiranavali on Praiastapada's Padarthardha rmasamgraha. The Subject discussed in Atmatativa-viveka is the acceptance or the rejection of the soul that constitutes a prominent demarcating line between the two sects of philosophical systems—brahmanical and the Buddhist. Udyana took a comprehensive note of Buddhist philosophy and is considered to be the last word in the controversy between Buddhism and Nyaya. The Atmatattvaviveka, therefore represents a landmark in the controversy between the Buddhists and the Naiyayikas.