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The Ki to Aikido
By an Amazon.com customer
Ki in Daily LifeKi in Daily Life by Koichi Tohei
Buy new: $15.00 / Used from: $8.96
A good start to understanding. Recently revised.
A Road That Anyone Can Walk: KiA Road That Anyone Can Walk: Ki by William Reed
Buy used from: $10.26
A more advanced treatise of Koichi Tohei and Ki principles.
The Mysterious Power of Ki: The Force Within                                                           LtureThe Mysterious Power of Ki: The Force Within Lture by Kouzo Kaku
Buy new: $55.00 / Used from: $11.99
A more scholarly look from the Japanese view. Ends with an enlightening essay by Kishimaru Ueshiba (Second Doshu).
Enlightenment Through AikidoEnlightenment Through Aikido by Kanshu Sunadomari
Buy new: $16.95 / Used from: $2.79
This is a close look at aikido founder Morihei Ueshiba's spiritual practices from his student Kashu Sunadomari.
Aikido and the Harmony of NatureAikido and the Harmony of Nature by Mitsugi Saotome
Buy used from: $16.81
A look at the spiritual side of Aikido from Shihan Saotome.
Ki in AikidoKi in Aikido by C.M. Shifflett
Buy used from: $21.49
Currently out of print, this is a good introduction for any beginner.
Aikido Exercises for Teaching and TrainingAikido Exercises for Teaching and Training by C. M. Shifflett
Buy used from: $26.99
More exercises from Ms. Shifflett. For both the instructor and student.
Ki: A Practical Guide for WesternersKi: A Practical Guide for Westerners by William Reed
Buy used from: $2.73
Explains Aikido and traditional Japanese Arts using Ki.
Japanese Yoga: The Way of Dynamic MeditationJapanese Yoga: The Way of Dynamic Meditation by H. E. Davey
Buy used from: $16.95
H.E. Davey is an American member of Tempukai. Tempu Nakamura who founded Tempukai is known as the "father" of yoga in Japan. Several prominent Aikido teachers studied at Tempukai as well as Hombu dojo. Davey illustrates the exercises and understanding of his Tempukai experience.
Hara: The Vital Centre of ManHara: The Vital Centre of Man by Karlfried Graf Durckheim
Buy used from: $9.98
An older book whose ideas are very contemporary.