Full Idea
There is this question of natural theology, how a sole Principle, all-good, all-wise and all-powerful, has been able to admit evil, and especially to permit sin, and how it could resolve to make the wicked often happy and the good unhappy?
Gist of Idea
How can an all-good, wise and powerful being allow evil, sin and apparent injustice?
Source
Gottfried Leibniz (The Theodicy [1710], p.098), quoted by Franklin Perkins - Leibniz: Guide for the Perplexed 2.IV
Book Reference
Perkins,Franklin: 'Leibniz: Guide for the Perplexed' [Continuum 2007], p.42
A Reaction
His answer is, roughly, that there is an unavoidable trade-off, which humans cannot fully understand. Personally I would say that if there is a God, the evidence for his benevolence towards humanity is not encouraging.