A question for the ages, eh? As for Blisterize's input, I was intended to get a rough estimate (which in reality is all a numeric derivative can find). Either way I'm glad he's working on it not me

As for our perception of free will. I tend to put this in the same catagory as our perception of time. It cannot be directly perceived, therefore we cannot emperically draw a logical conclusion. This is the realm of nothing more than speculation, unless you can apply some type of mathematics (I have seen this done once, but it was used to illustrative purposes not definitive)