Eternal oblivion is a permanent loss of conscious existence held by some to occur upon death. This outcome is typically associated with physicalist and atheist viewpoints that view consciousness as the mechanical result of a sufficiently complex thinking system, i.e. the brain, with one's subjective experience of personhood and reality therefore being irreversibly lost once such a system ceases function. This is in contrast to the spiritualist or religious view describing an immortal soul that maintains individual life and experience into an afterlife upon the death of the physical body. Conditionalism, annihilationism, and mortalism are viewpoints that make use of eternal oblivion within Christian theology.