Ai-Uchi Mutual Destruction

By Muromoto, Wayne
This article first appeared in the "SMAA Journal" Volume 24, Issue 3.
Ai-Uchi Mutual Destruction

Have you ever heard the term “ai-uchi” used in your martial art?

What does “mutual destruction” have to do with modern martial arts?

It is often used in kendo; fencing with bamboo staves, but you may hear it in old-fashioned karate schools and the like. Ai-uchi, to most practitioners, simply means the two sides strike each other at the same time, so their points cancel out each other in a contest.

Sasama Yoshihiko, in Zusetsu Nihon Budo Jiten, offers a more in-depth definition. One old meaning of the term is actually a kind of gangtackling an enemy. When two or more people attack a single enemy at once, it is called ai-uchi, the ai (meaning “mutuality”) now meaning “group” attack. Like a kind of “swarming” used by police to subdue an unruly prisoner. Old records document instances of sannin-ai-uchi (three against one) and two against one attacks on the battlefield, in which groups of two or three footmen gang up and take down one samurai.

But the meaning of most importance to martial artists is the concept of ai-uchi as “mutual strikes.” Your strike hits the opponent the same time as he strikes you. So theoretically, both of you die.

There are a number of things to consider concerning ai-uchi. In a sportive contest of point-taking, like kendo or karate, it's a lot of fun to just go at it and strike the opponent without fear of much bodily injury, thanks to rules and protective gear. But the samurai were a conservative lot. Their philosophy of fighting and combat—which may surprise modern day martial arts people who strut and preen about their willingness to fight with anybody—was very, very reserved.

Their conclusions were that there were three things that can result from a real battle, and two out of three were very, very bad. The good result is if you win and the other side dies. The really bad result is if the other guy wins and you die, and finally the third is still bad news for you; ai-uchi is when both of you kill each other off.

Now, two out of three chances of killing your enemy might not be bad if you're fighting to defend someone else, and you're willing to sacrifice yourself to save your lord and/or loved ones from the enemy attacker, as long as you destroy the other guy. But in terms of self-preservation, these are really lousy odds.

So really philosophical warriors, who thought about the consequences a lot, were quite reluctant to engage in real combat at the jump of the hat. Even if they were technically very good, there's no telling what chance and luck may bring to you . . . you could slip on a banana peel, for example, and so the lousiest warrior for the other side could take your head. If he did have to go into battle, the classical warrior was pretty much resigned to accepting the fact that the odds were two to one that he'd be dead come the next day, all other things being equal. 

Say you have overwhelming firepower. You can maneuver as you want to outflank the enemy and obtain every advantage, which one might say is a kind of philosophy of outmaneuvering and unbalancing. But if the enemy and you meet on a field of battle, and he attacks you at the same time you attack, you will probably absorb some losses. But if you can destroy the opponent, whacking him harder than he whacks you, you will win the day. So, in this battlefield ai-uchi, you will accept some losses with the intention of inflicting a lot more losses on the enemy as both of you attack at the same time.

In real life terms, perhaps it means that no matter what, you win some, and you lose some. And sometimes you get just as much as you give. Or more.

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