Christians believe that ours is The Best of All Possible Worlds, an idea that comes to us from Gottfried Wilhelm Leibniz, the man who discovered calculus around the same time as Newton did. In this essay, Michael Dirda reviews a book by the same name, The Best of All Possible Worlds: A Story of Philosophers, God, and Evil by Steven Nadler. The questions behind that phrase are, Did God make evil? Why does evil exist? If God is good, why do bad things happen? These questions are simplistic, but completely realistic, too.

The attempt to justify the ways of God to men — theodicy, a term coined by Leibniz — lies at the heart of the matter: “Why is there any evil at all in God’s creation?” Essentially, Leibniz’s answer is: Consider the whole [...] As Nadler emphasizes, summarizing Leibniz, “all things are connected and every single aspect of the world makes a contribution to its being the best world.”

That includes what we call evil.

However, Leibniz offers no explanation of just how evil assists the overall goodness of things. (Sometimes he even seems to suggest that it serves to bring the good into greater relief.) We cannot penetrate so far into the Creator’s mind or plan. Still “it is inconceivable . . . that an infinitely good and perfect God could choose anything less than the best.” This conclusion may satisfy a devout Christian philosopher, but it offers scant consolation when we are in pain, or see the wicked succeed and the worthy fail, or when we face death.

True, true, but it’s heartening that this question still fires the imagination of people who write books and review them and read them. That’s enough proof, for now, that the world still has something good in it.