Go no sen

Go no sen (Japanese: 後の先, post-initiative) is a concept of Japanese martial arts in which a combatant takes the initiative in a fight after the opponent has already started an attack. In other words, once the opponent starts to attack, the defending combatant performs this technique. The Go no sen technique can take various forms, since it depends on the use of the energy and momentum of the attacker.

This is not just counter-attack. Go no sen is a mental state, a level of concentration assumed during combat. It is more correct to say that it is a harmonization with the very movement of attack, not just defense.

One of the methods to grab ki is to wait for opponent's move, and once it has been made, the defender takes the strength used by the attacker, not opposing it but rather making it go to one side or turning it back on the attacker. For this, it is necessary to capture the move at the right moment. There must be harmony between the fighters, in order to capture the ki of other. If the opponent is simply opposed, there will be only shock and loss of strength for both, but otherwise, if there is harmony, this loss will be limited to that one who attacks.

Besides the martial aspect, go no sen can be seen as part of a philosophical and moral code, emphasized when one considers the term "DO" (道, dō), meaning that the budoka should never take the initiative in an eventual and inevitable confrontation. In karate, it is seen in the sentence "in karate there is no first strike" (空手に先手なし, karate ni sente nashi).