Chapter III: , sections 12-13. Read "The Inadequacy of the Psychological

Standpoint," "System of Metaphysics," Chapter II. I call especial attention to the illustration of "the man in the cell" (pp. 18 ff.). It would be a good thing to read these pages with the class, and to impress upon the students the fact that those who have doubted or denied the existence of the external material world have, if they have fallen into error, fallen into a very natural error, and are not without some excuse.