An article in the Independent which questions whether we actually have free will, might hurt your brain trying to fathom out. Scientists in the Scientific American magazine say that the idea of free will may have arisen because it is a useful thing to have, giving people a feeling of control over their lives and allowing for people to be punished for wrongdoing.
However scientists believe that it might only be quickly made choices that don’t require much thought where we really have choice, and in fact bigger decisions might give the illusion of choice even when there isn’t. Complicated arguments.
We use the argument of Free Will quite regularly in our GCSE RS answers because it can explain why people, and Christians, might make their own decisions about a moral situation and not necessarily follow the Bible, Church and Situation Ethics. It allows us to understand that people decide on their actions and they are not puppets to a greater being like God: