Lots of folks like to assert that you cannot prove a negative, but this is a completely and obviously self-defeating position. We can prove that there are no cows in my apartment right now and that I cannot fly upwards at will or that there are no square circles. We might also point out that some of the most basic principles of logic are stated as negatives like the law of non-contradiction - No proposition can be both true and false at the same time and in the same respect. So, this leads me to a question: which argument for the non-existence of God do you think is the best? Does gratuitous evil mean that God's existence is improbable or the best explanation of experience? Does the apparent incompatibility of divine properties like all-loving vs. immutable, immutable vs. personal or non-physical and personal mean that God cannot exist? Any thoughts on this topic?