As such, it refers to not just an unbalancing, but the process of getting an opponent into a position where his stability, and hence ability to regain compromised balance, is destroyed. Maai refers to the space between two opponents in combat. It is a complex concept, incorporating not just the distance between opponents, but also the time it will take to cross the distance, angle and rhythm of attack. It is specifically the exact position from which one opponent can strike the other, after factoring in the above elements. For example, a faster opponent's maai is farther away than a slower opponent. It is ideal for one opponent to maintain maai while preventing the other from doing so. Masakatsu agatsu is a 4 character compound expressing a concept in Japanese martial arts, particularly aikido, referring to the true victory of self-mastery. It was a common saying of aikido founder Morihei Ueshiba which emphasizes that aikido is not a competitive martial art like judo or taekwondo. Shinmu fusatsu states that in aikido one should not kill the opponent. It is related to the kenjutsu concepts of satsuninto (殺人刀 the sword that takes life; also satsujinken 殺人剣) and katsujinken (活人剣 the sword that gives life). Taisabaki relates to 'whole body movement', or repositioning. It can be translated as body-management. It is a term used widely in kendo, jujutsu, aikido, judo, karate and ninjutsu. Tai sabaki is usually used to avoid an attack, such that the receiver of the attack ends up in an advantageous position and it is often wrongly referred to as "evasion." Takemusu was the concept developed by Morihei Ueshiba of how the ultimate martial art should be, how his aikido should be, an art which may harmonize all living beings and free techniques could be spontaneously executed. In his latest years, Ueshiba developed the more spiritual aspects of his art and even adopted the name Takemusu Tsunemori, under which he left many paintings and poems. Tenkan is a 180-degree pivot to one's rear, on the lead foot. Zanshin refers to a state of awareness – of relaxed alertness. The literal translation of zanshin is "remaining mind". Zanshin sometimes refers more narrowly to the body's posture after a technique is executed. Yamabiko The concept of calling out the attack rather than waiting for the attacker. The term presumably comes from a poem by the founder. It is loosely related to