| I used to have a firm scientific worldview, but now I'm not so sure.
Given the principle that everything in the universe obeys scientific laws, then every scenario can have only one result. The result of any scenario is whatever the laws of nature predict will be the outcome. If given the same initial conditions and the same laws, then the result should always be the same. This is known as determinism.
If we look around our world, everything behaves as we expect it to. A ball rolling downhill doesn't suddenly start rolling uphill for no apparent reason. Billiard balls bouncing around on a table go where their velocities and collisions take them.
The only exception to a totally predictable world appears to be actions taken by conscious organisms. It can be argued that conscious decisions are also following natural laws - that chemical and electrical interactions in our brains always leads from one train of thought to another. If that is true, then everything could really be inevitable, as hard determinism suggests.
While hard determinism is not something I rule out, I do also experience the appearance that my choices are free, that I have free will, that they are not completely dictated by my previous thoughts. This may only be an illusion - I do not know.
It can be argued that quantum effects contradict the reasoning for determinism. However, quantum effects do not manifest themselves in the larger world. Large objects behave predictably and not randomly. Thoughts follow one another and are not randomly jumbled together (unless you stop taking that medication =)
So with the assumption that all non-conscious objects behave in an inevitable manner, the only thing that can prevent all of history from being predetermined at the dawn of time (by the laws of physics and the initial conditions) is consciousness. If consciousness and free will are illusions and not the miracles they appear to be, then there really is nothing that could have prevented me from thinking these thoughts and writing what I'm writing.
I see evidence for both possibilities and I can't rule either out, but if free will does exist, then something besides the laws of causality must be responsible for it.
And that would be a miracle. | 
