However, we can't ever definitively 100% prove any negative, ever. For instance, I want you to prove that Mickey Mouse isn't sending coded messages directly into my brain telling me to obey the Freemasons.
I think it would profit this discussion to think about what science has to say about good ol' mickey. Because science utilizes inferrence to the best explanation, a scientist would start by questioning what is making you say these awful things about mickey mouse (God bless him). After looking at the signs - an MRI, a cat scan, abnormalities in behaviour, evidence of halucinations - and symptoms - depression, headaches - a scientist would suggest the natural explanation that best maps the data. He might say that you are schitzophrenic, but he would rely on a natural explanation that could be falsified, unlike Mickey Mouse. So at the end of the day, science only posites claims that are falsifiable, thus it has no need to posite God.
However, individuals often feel obliged to posite God, and rightfully so. Their intuitions tell them that there is more to life than science can tell them. For instance, science can tell us a lot about the way things are but cannot tell us about the way things should be Thus people draw on a concept of God for morality and meaning. Some people, on the other hand, simply make the metaphysical claim that a mind precedes order. Unlike the Intelligent Design crew, this argument is not based on "scientific evidence," it is more like a synthetic a priori claim. Other people make the equally justified claim that order is simply a brute fact. Both positions are equally burdened with assumptions. At the end of the day, you can never prove that there is a God, especially using science, but this belief is as justified as believing that there is not a God.
™ Version 4.2