Complex sentence: Self-persuasion permits a person's mind the ability to be influenced or persuaded if they choose so, the mind through persuasion can also deny or resist if it so chooses to do so, regardless of self-persuasion.
Split into simpler sentences: Self-persuasion permits a person's mind the ability to be influenced or persuaded if they choose so. The mind through persuasion can also deny or resist if it so chooses, regardless of self-persuasion.