  Norris offers an important insight into how the real distinction proof depends on abstractive processes. However, like Malebranche, Norris claims that we have no access to God's idea of the mind.  The mind's existence is known only by inner consciousness, or sentiment. This raises the same problems for Norris that Malebranche has defending the proof. (See Nolan and Whipple 2005.) If humanity is ignorant about the essence of the soul, then there can be no proof using the essence of the soul as a premise; we cannot know if the proposition, ‘The mind is a substance’, is true or false.  At best, it is indeterminate. So, whether Norris can fully defend the proof is questionable. Nonetheless, Norris argues for the immortality of the soul in A Philosophical Discourse concerning the Natural Immortality of the Soul in response to a work published by Henry Dodwell. Dodwell held that all souls are material, and only a few souls are granted immortality. Norris, relying upon the essence of the soul as immaterial, draws a distinction between the indissolvible and the imperishable (33–34). The soul is naturally indissolvible because it is indivisible, but it is not imperishable. If God ceased his constant creation, all things would immediately cease to exist.