Absence is the key image for her metaphysics, cosmology, cosmogony, and theodicy. The development of process theology has presented a challenge to the Irenaean theodicy. Immanuel Kant wrote an essay on theodicy. The Augustinian theodicy supports the notion of original sin. Theodicy () means vindication of God. The "Theodicy" was deemed illogical by the philosopher Bertrand Russell. At the core, apocalypses are a form of theodicy. John Hick criticised the Augustinian theodicy when he developed his own theodicy in 1966. In the twentieth century, John Hick collated the ideas of Irenaeus into a distinct theodicy. Voltaire also includes the earthquake/theodicy theme in his novel "Candide". In contrast, Pentecostal churches adopted the theodicy of misfortune. Augustine of Hippo was the first to develop the theodicy. The Irenaean theodicy is a Christian theodicy (a response to the problem of evil). Another major theme concerning "Blood Meridian" involves the subject of theodicy. Responses to the problem have traditionally been discussed under the heading of theodicy.