Earthquakes expose shaky foundations

The earthquake and tsunami in Lisbon, Portugal in 1755 shook the philosophical foundations of many.   It led Voltaire to write the novel Candide, a critique of Leibniz's Theodicy which claimed that we lived in "the best possible of all worlds". This optimism (in the sense that the world is optimal).

                                              The Ruins of Lisbon

Karl Barth also critiques the "optimism" of Leibniz at the end of volume 3.1 of Church Dogmatics. He points out there is a triangle of God, man, and the world and different people start in different corners to formulate their view of the world. Barth claims that Leibniz and his fellow "optimists" had great confidence in their ability to look at the world and claim that it was "self evident" that is was "perfect". In contrast, a Christian claims the world is good, because God has declared it to be so, and in quite a different sense.

This impotence in self-confidence is the real disease of the 18th century. For all that it was felt so deeply and proclaimed so loudly its confidence was vulnerable. An earthquake could set everything in a new and different light. And it is symbolical and symptomatic that of all possible disasters it was an earthquake which brought about this change. It was fatal for these eternal observers and spectators that they should suddenly feel shaking beneath them the earth on which they thought they could calmly make their observations. What were they, what was the significance of their interpretation, when they were no longer sure of themselves? 

Real certainty depends on whether the ground on which we see and think is solid or unstable. We have seen that the Christian affirmation of the justification of existence gains its certitude from the fact that those who utter it have themselves been so seized upon and transformed that they cannot do other than affirm this belief. They have been brought to the point of decision. They are not just spectators but sworn witnesses to the perfection of the created world. They have been reached and pierced by the self-declaration of their Creator. They have been sought and found and chosen and called by Him. At the heart of creation He Himself has come to them, and grasped them, and committed them to the verdict of His good-pleasure, so that their minds and lips can know no other. Confronting God, they must also confront the truth of all things. And this fact implies the freedom of their judgment in face of shattering disturbances which inevitably affect observation and reflection that are free only in appearance. In this sense, too, the Christian affirmation says something different from that of pure optimism.

Karl Barth, Church Dogmatics 3.1: The Doctrine of Creation, p.  412

He then goes on to point out that Leibniz's problem was that his views were shaped by a generic God rather than using Christ as their starting point.