I don't recall you ever tearing it to shreds. There is only one possible future in a totally physically based system. Randomness cannot exist in it. Any "random" number generator" has a design. That design determines what the outcome will be. It might be more complicated than someone could consciously understand well enough to know it isn't really random, but it still isn't random.
A totally physical universe would be like one massive computer program. There is only one possible outcome at any given moment, unless acted upon by an outside force. The player is that outside force. You could also insert a generator inside of it that starts its sequence based upon the time, or if more advanced, the temperature, the humidity, the atmospheric pressure, ect. Perhaps you could design each circuit to be a little different, to make certain connections happen more often, or make outcomes happen based upon electricity spikes in your power.
You cannot have free will in a fully contained system from which all things in it originated as a result of everything that happened in that system with all of the materials and therefore the limitations in it.
The idea of a totally physical reality and free will are mutually exclusive.
You cannot logically have both.
Everything in a system is interconnected and affects everything else.
Nothing in a totally physical universe can be totally independent from anything else. Everything affects it and determines it's ultimate outcome.
Souls are intelligences that exist independently from the system and thus can resist many influences in the environment. In a totally physical universe, nothing is independent.
You can only have an independent consciousness in a system if your consciousness was created independently from it.
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