Illustrations
| 1. Nervous system: | 26 |
| 2. Reaction time: | 28 |
| 3. Unconditioned reflex: | 29 |
| 4. Conditioned reflex: | 29 |
| 5. Object and image: | 32 |
| 6. Gravity and weight: | 37 |
| 7. Center of gravity of a standing object: | 37 |
| 8. Center of gravity of a suspended object: | 37 |
| 9. Finding the center of gravity in a triangle: | 38 |
| 10. Finding the center of gravity in a trapezoid: | 38 |
| 11. Center of gravity and stability of a standing object: | 39 |
| 12. Center of gravity and instability of a standing object: | 39 |
| 13. Relative stability of standing objects: | 39 |
| 14. Right natural posture (migi-skizen-tai): | 41 |
| 15. Main natural posture (shizen-hontai): | 41 |
| 16. Center of gravity in main natural posture: | 41 |
| 17. Stability of main natural posture: | 41 |
| 18. Main defending posture (jigo-hontai) and its stability: | 41 |
| 19. Hiza-guruma (knee wheel): | 41 |
| 20. Kuzushi (off-balancing): | 41 |
| 21. Happo-no-kiiziishi (eight directions of off-balancing): | 43 |
| 22. Dynamic coordination: | 48 |
| 23. Coordination of forces: | 48 |
| 24. Uki-otoshi (floating drop): | 49 |
| 25. Combination of forces increases speed: | 49 |
| 26. Right-triangle sitting position: | 52 |
| 27. Right-triangle standing position: | 52 |
| 28. Right-triangle kneeling position: | 53 |
| 29. Stepping forward in right-triangle position: | 53 |
| 30. Improper posture hampers use of abdominal force: | 55 |
| 31. Defending posture does not permit quick movement: | 55 |
| 32. Law of reaction: | 62 |
| 33. Law of reaction: | 63 |
| 34. Kicking force K produces reaction force F: | 63 |
| 35. Force of momentum: | 66 |
| 36. Force of friction: | 66 |
| 37. Muscular contraction: | 67 |
| 38. Partial and total muscular force: | 67 |
| 39. Using force of gravity to assist in a throw: | 69 |
| 40. Center of gravity at fulcrum: | 69 |
| 41. Momentum plus muscular force beats muscular force alone: | 71 |
| 42. Momentum supplements muscular force in a throw: | 71 |
| 43. Impulse and impulsive force: | 72 |
| 44. Harai-goshi: less effective means of inducing momentum: | 74 |
| 45. Harai-goshi: more effective means of inducing momentum: | 74 |
| 46. Friction varies with weight: | 76 |
| 47. Friction assists in defense against a throw: | 78 |
| 48. Transmissibility of force: | 81 |
| 49. Transmissibility of force: | 83 |
| 50. Parallelogram of forces: | 83 |
| 51. Composition of forces in a throw: | 83 |
| 52. Decomposition of forces: | 85 |
| 53. Modified kami-shiho-gatame uses larger vertical component: | 85 |