From the last post, I want to move to the best of all possible worlds theodicy. One of the strengths of this theodicy is how straightforward and precise it is. It is also traditionally recognized as one of 18th-century philosopher Gottfried Wilhelm Leibniz’s highly essential contributions to philosophy of religion. The place to start is God’s omniscience. This allows God to understand all possibilities. If God knows all possibilities, God knows all possible worlds. God is likewise completely good and so constantly aspires the best and continuously performs in the best way. Leibniz writes, “The first principle of existences is the following proposition: God wants to choose the most perfect.” The power of the best-of-all possible-worlds theodicy is to demonstrate God’s decision to generate this world out of every world that he could have produced, for this creation is good. Nicholas Jolley writes, “The philosophical moral, then, is that whatever God creates is good, and this is equivalent (by contraposition) to saying that whatever is good is not created by God.”
Leibniz ties in several principles to the theodicy. The first major principle is centered on the truth God acts for worthy causes. Again, God’s omniscience presumes God understands the value of every world possible prior to deciding which one to produce. This also implies God always decides on the base of sensible, stable rationales. This is called the “principle of sufficient reason.” Leibniz purports,
Now this supreme wisdom, united to a goodness that is no less infinite, cannot but have chosen the best. For a lesser evil is a kind of good, even so a lesser good is a kind of evil if it stands in the way of a great good; and there would be something to correct in the actions (so, the omnipotence) of God if it were possible to do better.
To believe God can intercede in what he has formed with sufficient reason, even to avoid or restrict evil, would be akin to a soldier who abandons his post during a war to stop a colleague from perpetrating a slight violation.
Leibniz does not leave the principle of sufficient reason to fend for itself. Instead, he reinforces the best-of-all-possible-worlds theodicy with the principle of “pre-established harmony.” He describes it this way: “For, if we were capable of understanding the universal harmony, we should see that what we are tempted to find fault with is connected to the plan most worthy of being chosen; in a word we should see, and should not believe only, that what God has done is the best.” In other words, God performs corresponding to divine perfection and liberty, decides to produce, commands creation corresponding to this nature, and then can choose a world that includes evil. Living in the best of all possible worlds requires the world to comprise the best goods out of any, with the greatest harmony. Jill Graper Hernandez states, “The mere existence of humans in creation requires that humans may choose certain evil acts, and this is harmonious with God’s perfection of intellect and will.”
 Each possibility is a new sphere, or world, of possibility that varies from the world we presently occupy. A possible world comprises an extensive idea of God’s intelligence that completely explains what could have happened if that world was generated (Jeffrey K. McDonough, “Leibniz: Creation and Conservation and Concurrence,” Leibniz Review , 33).
 G.W. Leibniz, “On Freedom and Spontaneity,” Academy ed., VI 4-b, 1454 in The Shorter Leibniz Texts, ed. Lloyd Strickland (New York: Continuum, 2006)
 God describes everything he created as “good.” See Genesis 1.
 Nicholas Jolley, Leibniz (New York: Routledge, 2005), 618.
 Jill Graper Hernandez, God and Evil: The Case for God in a World Filled with Pain, ed. Chad Meister, James K. Dew Jr. (Downers Grove, IL: InterVarsity Press, 2013), 100.
 G.W. Leibniz, Theodicy, ed. Austin Farrer, trans. E.M. Huggard (New Haven, CT: Yale University Press, 1952), II. 8.
 Causa Dei, in Leibniz: Monadology and Other Philosophical Essays, ed. and trans. Paul Schrecker and Anne Martin Schrecker (Indianapolis: Bobbs-Merrill, 1965)
 G.W. Leibniz, Theodicy, ed. Austin Farrer, trans. E.M. Huggard (New Haven, CT: Yale University Press, 1952), I. 44.
 Jill Graper Hernandez, God and Evil: The Case for God in a World Filled with Pain, ed. Chad Meister, James K. Dew Jr. (Downers Grove, IL: InterVarsity Press, 2013), 101.