We believe that "free will" and "determinism" are relative, in that observers may view both aspects within the same system, depending on their location and other attributes. For instance, the "free will" of a photon going through a double-slit apparatus may vary depending on how one formulates the underlying physics, where one is observing the photon, and other factors. Mathematically sufficient theories are "correct", therefore we believe on may ultimately derive both "deterministic" and "free will" versions of the system, and both are thus valid to the observers involved.