@jpl458 - if I may step into that question, Jon and I have debated the issue a few times, as have others.
My take is two-fold.
FIRST, since we do not know the precise workings of the human mind, even though we may be able to guess at someone's most likely actions, the fact that we cannot do so with real accuracy suggests that we still have available to us a range of behavioral variations that might as well be free will, since we cannot predict a person's actions.
SECOND, because things occur at the molecular level, and memory has to change the brain in a permanent way (otherwise we would forget something as soon as we learned it), we have to consider that chaos theory comes into play. Including sensitive dependence on initial conditions. At longer term, sensitive dependence on
prior conditions. We would have to know EVERY INFLUENCING EVENT in a person's life to predict actions. We have enough trouble remembering our own personal history in precise detail. Therefore I believe that what we have is technically indistinguishable from free will.
There is a fine line between behavioral psychology and fortune telling. Somewhere in the gap lies free will.