What I was arguing is that if we assume your position then we cannot even affirm your position, because it would be a position that would be determined by prior brain state and chemical reaction.
New thoughts can have antecedent causes.
We never invented laws of nature, we just discovered what was already there. In other words, everything you do or think is determined by prior causes. Tell me, how is this in any a ligitament approach to truth. Science, however, can never prove anything absolutely. Again though, none of this supports an idea of free will.