気
を付ける、残心、中心する、意識, 無心、ki wo tsukeru, zanshin, chushin suru, ishiki, 
mushin, paying attention, staying alert, being focused、awareness.
These
 are terms that everyone has come across in budo training.  Some, like 
ki wo tsukeru and zanshin are heard regularly, others aren’t heard as 
often but are just as important.  Budo is all about physical technique 
though, so why should we spend our time on mental areas like these? 
 Physical technique is great, but it is the mind that is the true weapon
 and how we train that is even more important than how we train the 
body.
Many
 of the things that change average technique to great technique are not 
technical.  They are mental.  Doing things like controlling timing and 
spacing begin with mental awareness and focus.  I don’t care how good 
your technique is, if your timing or spacing are off, the technique is 
worthless.  Understanding timing and spacing is mental.  It’s about 
awareness and focus.  This is where practice gets interesting.  Learning
 another armbar variation, or another way to do kiriorshi frankly 
doesn’t teach you very much that can be applied anywhere except in the 
very closely defined realm in which it is learned.
Learning
 to let go of all the stuff cluttering up your mind so you can pay 
attention, stay alert, be focused and aware of the world is tough stuff.
  I’m still learning how to do it.  One of the nice things about budo 
practice is that the correction is usually really fast when you lose 
focus and let your alertness, your awareness, go.  I’ve gotten hit in 
the head more than once because I wasn’t paying proper attention.  The 
physical practices should lead us into the mental ones.  
In
 budo we often talk about zanshin 残心 and mushin 無心。  You’ll notice that 
the last character is the same in both words.  It means heart/mind and 
represents “the psyche; the mind; the emotions” (definition form the 
Kenkyusha Online Dictionary).  In zanshin, the first character is for 
something that remains, that is left, that stays.  The idea is one of 
staying aware, staying alert, your mind remaining on the situation at 
hand.  In koryu bugei, as well as in kendo and many other modern budo 
styles, the idea is that the kata doesn’t end when the action ends.  
You
 have to stay aware and focused even after the fight is finished.  Even 
though you have ostensibly won, you can’t just relax and let  your focus
 go rushing away.  The action might not be over yet.  What if your 
adversary has friends who come along suddenly?  Or what if the adversary
 isn’t quite finished? If  you just relax, drop your guard and start 
thinking about how glad you are that the fight is over, you will be 
surprised by anything that comes next.  The Muso Jikiden Eishin Ryu kata
 called Yaegaki
 is a great example.  The kata assumes an adversary directly in front of
 you.  Once she has been dispatched, you start to sheath your sword. 
 When it’s almost all the way back in the saya, the adversary rallies to
 take a swing at your leg.  If you have relaxed, you won’t be able to 
respond in time to save your leg.  If you are still aware, if you are 
practicing zanshin, you can.  
All
 koryu bugei kata that I am aware of require that the student practice 
maintaining awareness, zanshin, even when the action is over.
Really
 though, the training is to be aware from well before the action starts.
  In kneeling kata like Yaegaki or the much less complicated Mae, the 
kata doesn’t begin when the action starts.  It begins at the moment you 
start to kneel.  In paired kata, such as in  kenjutsu, the kata starts 
as soon as you bow to your partner, and it doesn’t end until you’ve 
moved apart and bowed to signal the end.  I have memories nearly as 
vivid as the bruise I got one day when my attention wandered after the 
action of a kata was finished and my partner, the instructor, recognized
 this and caught me in the solar plexus.  I had dropped my attention 
because we were “done”.  Except that we weren’t.  We were still close 
enough together to be immediate threats, and I should have been 
maintaining zanshin.  I wasn’t, it was clear to my partner, and he gave 
me a gentle reminder.
Zanshin
 is focused awareness, but it’s not so narrowly focused that you forget 
about the rest of the world.  You have to be aware of what is around you
 at the same time that your attention is focused on your adversary. 
 This is the mental extension of the metsuke
 that I wrote about previously.  With metsuke, you want to keep you keep
 focused on your adversary, but you can’t lose your peripheral vision 
and awareness of your entire opponent.  If you only look at his weapon, 
you miss what he’s doing with his body.  If you only look at his face, 
you don’t know what he’s doing with his weapon.  The saying in budo is enzan no metsuke 遠
山の目付, or roughly, “looking at a far mountain”.  The idea is that your 
gaze is focused on one point, but your peripheral vision is still active
 and taking in the whole of the scene.  In budo, the idea is that you 
are focused on your partner but you can still see his entire body and 
weaponry in your peripheral vision.
This
 focused awareness, in my experience, is something like this.  Your 
attention is fully focused on your partner, but you are still aware of 
your surroundings as well.  In the dojo you don’t want to move into the 
way of another group who are also training, you don’t want to run into a
 wall, and you don’t want to hit anyone you aren’t training with at that
 moment.  I first experienced this type of awareness at judo practice. 
 During randori (open grappling practice in this case), the mat would be
 filled with grappling pairs, most standing, and a few on the ground.  I
 had to be completely focused on what my partner was doing while at the 
same time being aware of the people around me on the crowded mat.  
At
 first I had trouble just keeping my attention on my partner. I would 
drift back into my own mind thinking about what to do and immediately 
get thrown.  I didn’t have enough awareness to encompass my partner and 
the rest of the people on the mat.  Fortunately, my partners generally 
did.  Gradually my ability to focused improved, and then my awareness 
started to expand.  I learned to be aware of the world around me without
 taking my attention off of my partner
This
 is a part of zanshin. You have to maintain your focus on your partner 
without losing your awareness of the rest of the world.  In solo iai 
practice, the reasons for this can be made explicit; they adversary may 
not be finished, or there may be other adversaries still around.  It’s 
more difficult to model this in paired kata, but the aikido training 
technique of multiple attacker randori can do a good job of this.  You 
have to remain aware.  Zanshin.  残心.
This
 whole line of thought was kicked off by a piece I read in which the 
author talked about trying to make a list of things to do while she did 
dusted the dojo.  Since dusting didn’t require her focus or real 
awareness, she tried to do other things like make to-do lists with her 
awareness.  One of the long, slow lessons I have taken from studying 
budo is that whatever I am doing, just do it.  I don’t have enough 
awareness to spread it out to multiple activities and do any of them 
well.  The more I practice just doing one thing and being aware of what I
 am doing, the better I get at it.  
This
 is a lesson that is not unique to budo, but is fundamental to any of 
the Ways.  In fact, it’s one that is probably better taught in other Way
 traditions such as shodo and sado than in budo.  In calligraphy and tea
 ceremony, the practice of focusing on what your are doing, and only 
what your are doing, is right out in front.  In budo it’s awfully easy 
to get tied up in the cool techniques and dealing with an opponent and 
forget to be focused and aware of what we are doing.  
Zanshin
 is helpful in just about anything we do, even simple, mundane tasks 
such as dusting.  I find that the simple tasks get done faster and 
better when I am mindful of what I am doing.  If I let my mind go 
flitting wherever it pleases, I miss details of what I’m doing and end 
of doing a poorer job than I can.  But the other benefit of doing simple
 tasks mindfully is that I am practicing being mindful and aware of what
 I am doing.  The more I practice this with simple tasks, the easier it 
becomes with more difficult, complex tasks (like trying to catch the 
tsuka of sword while the swordsman is trying to hit me with the sword). 
 And as I get better at mindful awareness in the dojo, the better I am 
at applying it throughout the rest of my life.
That’s
 the thing about training a Way, whether it is budo or sado or shodo or 
kado or any of the others.  The training is not just about the 
particular isolated skill of fighting or making tea or writing pretty 
characters or arranging beautiful flowers.  It’s training for all of 
life.  In this case, it is training our mind how approach and deal with 
any task, to be focused and aware of what we are doing, but not so 
absorbed that we forget the whole world.  We have to remain aware.