Best of all possible worlds

The phrase "the best of all possible worlds" (French: le meilleur des mondes possibles; German: Die beste aller möglichen Welten) was coined by the German polymath Gottfried Leibniz in his 1710 work Essais de Théodicée sur la bonté de Dieu, la liberté de l'homme et l'origine du mal (Essays on the Goodness of God, the Freedom of Man and the Origin of Evil). The claim that the actual world is the best of all possible worlds is the central argument in Leibniz's theodicy, or his attempt to solve the problem of evil.

Among his many philosophical interests and concerns, Leibniz took on this question of theodicy: If God is omnibenevolent, omnipotent and omniscient, how do we account for the suffering and injustice that exists in the world? Historically, attempts to answer the question have been made using various arguments, for example, by explaining away evil or reconciling evil with good.

As a Christian, Leibniz outlined his perfect world theory in his work The Monadology, stating the argument in five parts:

To further understand his argument, these five statements can be grouped in three main premises. The first and second statements state that God can only choose one universe from the infinite amount of possible universes. The third and fourth statements state that God is a perfect existence, and he makes decisions based on reason. The final statement, which is the conclusion, says the existed world that is chosen by God is the best.

Leibniz used Christianity to back up the validity of all the premises. For the first premise, God's existence and role as the creator of the world was proven by the Bible; the "one universe" argument does not necessarily mean that only one world could exist, that one can extend "universe" to mean the set of multiple worlds, which God is supreme over, and that this set is the best of all possible worlds. The second premise is proven since "God acts always in the most perfect and most desirable manner possible". Therefore, His choice will always be the best, and only perfect existence can make perfect decision throughout time. Since all the premises are right, then Leibniz concluded, "The universe that God chose to exist is the best of all possible worlds".

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