avidyā, ignorance, and in some senses Māyā, illusion; it is darkness without illumination, the ignorance which mistakes seeming for being, or illusory phenomena for realities; it is also intp. as 痴 ignorant, stupid, fatuous; but it means generally, unenlightened, unillumined. The 起信論 distinguishes two kinds as 根本: the radical, fundamental, original darkness or ignorance considered as a 無始無明 primal condition, and 枝末 'branch and twig' conditions, considered as phenomenal. There is also a list of fifteen distinctions in theVibhāṣā-śāstra2.avidyāis also the first, or last of the twelvenidānas.