If what I have just said is not enough to illustrate the difference between these two substances, one can read and meditate on some passages of Saint Augustine, such as chapter of the tenth book of The Trinity, chapten and of the Quantity of the Soul, or Descartes's Meditations, particularly the part concerned with the distinction between the soul and body, or finally, the sixth discourse from Cordemoy's Discernement de I' ame and du corps.