A considerable problem for most theistic systems is presented by the question of theodicy. God is usually portrayed as infinitely benevolent person who wishes good for everyone. Furthermore, he is also thought to be omnipotent or capable of anything possible. Given these premises, it would seem a necessity that God would eradicate world of all evil. Yet, the world is clearly full of evil things, and not just minor evils, like the pain that I got when my toe hit a stone, but also evil of major proportions, such as earthquakes and wars. These considerations thus present a challenge for anyone accepting the existence of omnipotent and benevolent deity.
Bilfinger considers the problem in the section of Dilucidationes concerning natural theology, but he had also dedicated for it earlier a whole treatise, De origine et permissione mali, praecipue moralis, commentatio philosophica. While apparently only about this particular question, Bilfinger takes considerable time defining and explicating all concepts involved in the problem and thus goes through a significant portion of other metaphysical issues. Thus, it is no wonder that central concepts for solving this problem are actually physical or psychological: causation and letting things happen.
Of the two concepts, causation appears easier to understand: if A does something that makes B happen, then A has caused B, that is, if my pressing the trigger leads to the death of the person, the pressing was the cause of the death and I am thus to be blamed. Being a cause of something then requires a) that the cause was active in causing something and b) that without this activity that which was caused wouldn't have happened.
Letting or allowing things to happen is then, in a sense, a concept contrasting with the concept of causation. The crucial difference lies in the clause a), which in this case would say that the allowing factor was in a sense passive or did not act in some manner. Furthermore, the clause b) would be otherwise identical, but instead of activity, the lack of activity is the crucial element required for the event. Thus, if I don't push a person away when she is about to be hit by a rock, I could be said to have allowed the rock to hit the person.
Now, it is clear that the notion of allowing something to happen is meaningful only from the perspective of conscious agents, who can be said to have considered whether to act or not. Thus, we wouldn't say that an immovable stone allowed a robbery to happen by not dropping onto the head of the robber, because stones usually don't have any say in how they happen to be moved.
An intriguing question, especially from the viewpoint of ethics and justice, is whether allowing something to happen should have the same status as causation. In one sense, causation is something more: I am punished by law, if I actively make bad things happen, but not if I allow them to happen with my own passivity. Thus, it is no wonder that Bilfinger adopts this distinction as a partial explanation of the problem of evil. That is, he argues that we couldn't blame God for all the evil in the world, because he hasn't really caused it, but merely admitted it within the world.
Bilfinger's justification might still not completely satisfy us. After all, we do sometimes reproach people also for not doing things, especially if they are very powerful and would have had the capacity to prevent some extreme evil to happen: politicians who do nothing for things such as pollution and poverty fall to this category. It appears preposterous to suppose that God Almighty could get away from all guilt merely by saying that he had nothing to do with the evil in the world, he just watched it unfold.
Bilfinger thus must also have recourse to the Leibnizian idea that God has chosen the optimally good of all possible worlds. Whatever evil there is, it should be just a necessary ingredient of and condition for ultimate goodness – and if we could see things from God's viewpoint, we could immediately see how all the seeming evil falls into a greater pattern of goodness.
What then is the real cause of evil, if not God? Ultimately, Bilfinger says, it all comes down to the finiteness or imperfection of the world and its denizens: only God can be perfect, so all things outside him might possibly lead to some evil consequences. God cannot be faulted for their imperfections, because imperfection is in their nature. Instead, God merely gave these finite substances actuality, which is positive in itself.
A particular source of evil Bilfinger emphasizes is free will: because humans and other conscious beings are imperfect, but free to choose their own fates, they might e.g. make their egoistic desires into maxims guiding their action. Evil following from perverted use of free will Bilfinger calls moral, distinguishing it from general metaphysical evil associated with finity and from physical evil.
The most problematic is Bilfinger's account of physical evil: if a stone falls on my head and kills me, I cannot blame the stone, because it had no choice in the matter. Some responsibility obviously lies with free agents: if I get angry to a person and drop a stone on him, it is my fault and not stone's. In these cases physical evil is just a consequence of moral evil, but it appears that a fair portion of physical evil is not of this kind: witness, for instance, earth quakes. True, we could suppose that there is an evil supernatural entity behind all such phenomena, but this seems overly complicated. Bilfinger himself adopts a different defense: physical evil that has not been caused by actions of a morally evil person is probably God's punishment for immoral life. Although this notion is consistent, I find it rather barbaric that a God would have to unleash earthquakes and volcanoes for punishing criminals.
So much for Bilfinger, next time I shall return to the beginning of the atheism controversy, that is, Wolff's lectures on Chinese philosophy.