I have simply claimed that the conscious will of my soul is responsible for the posts I make on this forum, because I can't envisage any other feasible explanation.

You claim that if my spiritual soul exists, whatever it does will be deterministic in the same way as physical brain activity. But if my free will actions are derived from my soul, you must at least admit that they will have a different origin (being spiritual) to anything produced from physical brain activity. So can I repeat my request for you to say what defines the ultimate source of my posts (and yours). This is not a distraction, but a fundamental issue concerning what drives the conscious free will of human beings.