 Ultimate reality is of two types: the compounded (saṁskṛta) ultimate, and the uncompounded (asaṁskṛta) ultimate. The uncompounded ultimate consists of (a) space (akāśa), and (b) nirvāṇa—analytical cessation (pratisaṁkyā-nirodha) and non-analytical cessation (apratisaṁkhyā-nirodha). These three ultimates are uncompounded as each is seen as being causally unconditioned. They are nonspatial concepts. These concepts do not have any physical referent whatsoever. Space is a mere absence of entity. Analytical and nonanalytical cessations are the two forms of nirvāṇa, which is simply freedom from afflictive suffering, or the elimination of afflictive suffering. These concepts are not associated in positing any thing that can be described as remotely physical. They are thus the concepts that are irreducible physically and logically.