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[edit] Ki:　気、氣

Mind. Spirit. Energy. Vital-force. Intention. (Chinese = chi) For many Aikidoka, the primary goal of training in aikido is to learn how to "extend" KI, or to learn how to control or redirect the KI of others. There are both "realist" and anti-realist interpretations of KI. The KI-realist takes KI to be, literally, a kind of "stuff," "energy," or life-force which flows within the body. Developing or increasing one's own KI, according to the KI- realist, thus confers upon the aikidoka greater power and control over his/her own body, and may also have the added benefits of improved health and longevity. According to the KI-anti-realist, KI is a concept which covers a wide range of psycho-physical phenomena, but which does not denote any objectively existing "energy" or "stuff." The KI-anti-realist believes, for example, that to "extend KI" is just to adopt a certain kind of positive psychological disposition and to correlate that psychological dispositon with just the right combination of balance, relaxation, and judicious application of physical force. Since the description "extend KI" is somewhat more manageable, the concept of KI has a class of well-defined uses for the KI-anti-realist, but does not carry with it any ontological commitments beyond the scope of mainstream scientific theories.