CHAPTER IV
SENSATIONS AND "THINGS"
15. Sense and Imagination. 16. May we call "Things" Groups of Sensations? 17. The Distinction between Sensations and "Things." 18. The Existence of Material Things.
CHAPTER V
APPEARANCES AND REALITIES
19. Things and their Appearances. 20. Real Things. 21. Ultimate Real Things. 22. The Bugbear of the "Unknowable".
CHAPTER VI
OF SPACE
23. What we are supposed to know about It. 24. Space as Necessary and Space as Infinite. 25. Space as Infinitely Divisible. 26. What is Real Space?