Abstract
The aim of this paper is to clarify Udayana’s logic in his theistic monograph Nyāyakusumāñjali , especially in the second chapter where he postulates as conclusion the existence of God. In the course of this postulation, Udayana gives as its reason such Nyāya theories as the extrinsic validity of cognition (* parataḥprāmāṇya ) and the creation and dissolution of the world (*s argapralaya ). The present paper first focuses on the argument over the creation and dissolution of the world, clarifying whether Udayana asserts its necessary occurrence or just its possibility. It then analyzes the precise logic of Udayana that generates the theistic hypothesis, comparing it with a logic called abduction which is put forward by Charles Peirce