Koshijutsu is the skill of attacks to muscle and nerve points in Japanese martial arts. Koshijutsu is a major component of taijutsu.
This art of nerve striking utilizes the knowledge of the human body's nerves and muscles. The striking of these point causes sharp pain, numbness, and through some vital points the martial artist can cause temporary paralysis and even death. One can use this knowledge to gain an advantage over a larger or maybe even more skilled opponent. For instance if the opponent is skilled in blocking strikes, one could start by striking the points on the limbs and slowing the adversary down bit by bit, working up to the more vital nerve points and incapacitating the opponent and allowing for escape. There are some occasions where the martial artist must defend themselves, the well being of a weaker ally or innocent person, in which the martial artist is taught to engage and fight.