Ultrafinitism is the antithesis of googology; it is the mathematical belief that the set of natural numbers is finite, and at some point numbers become large enough that they simply cease to exist. The philosophy is an extreme form of finitism, which states that infinite objects (such as the transfinite ordinals) are nonexistent. Ultrafinitists state that the natural numbers have an ending, because they have no physical realization and/or cannot be computed.