Without the soul/self nothing can exits, whatever that exists is dependent on the soul/spirit for its existence. There is no need to flatter oneself that every thought and fancy that he has is the product of his own volition. But since he is himself is the products of this soul/spirit/self , it would be illogical to the last degree to presume that his individual ideas and fancies are exclusively his own creations and have no relationship to the the soul/spirit/self which he and his experience of the world is but a product of it.
Mind is mere illusion created out of the soul/spirit/ consciousness, it would then be ridiculous to suppose that the thoughts and ideas of an individual experience cannot have an entirely independent existence without the soul .