This book examines what seems to be the basic challenge in neuroscience today: understanding how experience generated by the human brain is related to the physical world we live in. The 25 short chapters present the argument and evidence that brains address this problem on a wholly trial and error basis.

Preface.- PART I. TWO REALITIES.- Chapter 1. Solving Problems.- Chapter 2. Objective and Subjective Reality.- PART II. Computation; Chapter 3. Algorithms.- Chapter 4. Coding for Computers.- PART III. ARTIFICIAL NEURAL NETWORKS.- Chapter 5. Neural Networks.- Chapter 6. The Resurrection of Neural Networks.- Chapter 7. Reinforcement Learning.- Part IV. perception; Chapter 8. What We Perceive.- Chapter 9. Lines and Intervals.- Chapter 10. Angles.- Chapter 11. Lightness and Darkness.- Chapter 12. Empirical Ranking.- Chapter 13. Color.- Chapter 14. Colorimetry.- Chapter 15. Motion Speed.- Chapter 16. Motion Direction.- Chapter 17. Size.- Chapter 18. Stereopsis.- PART V. Linking OBJECTIVE AND SUBJECTIVE.- Chapter 19. Stimuli and Behavior.- Chapter 20. Associations.- Chapter 21. Mechanisms.- Chapter 22. Reflexes.- PART VI. THEORIES.- Chapter 23. Feature Detection.- Chapter 24. Statistical Inference.- Chapter 25. Information Theory.- PART VII. SELF AWARENESS; Chapter 26. Awareness.- Chapter 27. Summing Up.