I by Karl R. Popper.- P1 Materialism Transcends Itself.- P2 The Worlds 1, 2 and 3.- P3 Materialism Criticized.- P4 Some Remarks on the Self.- P5 Historical Comments on the Mind-Body Problem.- P6 Summary.- II by John C. Eccles.- E1 The Cerebral Cortex.- E2 Conscious Perception.- E3 Voluntary Movement.- E4 The Language Centres of the Human Brain.- E5 Global Lesions of the Human Cerebrum.- E6 Circumscribed Cerebral Lesions.- E7 The Self-Conscious Mind and the Brain.- E8 Conscious Memory: The Cerebral Processes Concerned in Storage and Retrieval.- III Dialogues Between the Two Authors.- Dialogue I.- Dialogue II.- Dialogue III.- Dialogue IV.- Dialogue V.- Dialogue VI.- Dialogue VII.- Dialogue VIII.- Dialogue IX.- Dialogue X.- Dialogue XI.- Dialogue XII.- Bibliography to Part III.- Index of Names.- Index of Subjects.