I still don't think we have any kind of agreed upon definition of "Aiki". We have talked a lot about structure though.
Not yet. But, we've all read the threads about aiki is this and aiki is that. Even in this one, we both have completely different views and definitions on aiki.
However, we did find something of a common ground in structure. While structure alone isn't aiki, it is a component. That's a start.
So, rather than jump completely ahead of ourselves and bandy about definitions of aiki, how about we start building up to aiki with some of the components?
With structure, we can see that it isn't just about being solid and resisting someone like a boulder. That'll just get you punched in the face. Resisting someone with muscular strength isn't structure. It's the opposite. Structure is the ability to withstand force while remaining 100% mobile.
Can everyone do that? And some of the answers will be yeah, of course. But, can everyone do that without resorting to timing and rhythm?
In a very basic exercise:
Can you replicate your push test with arms out (uke pushing on the right hand) and then pivot like I did on the non-loaded foot? Yes, it's easy to let the push go from right hand to left foot and let all the load be dedicated to the left foot. Everyone can replicate that but it isn't mobile. That left foot is pinned to the ground. So, structure must include mobility. To continue with a very basic exercise, while receiving the push from right hand outstretched, one must be able to:
1. pick up that left foot and move it without being pushed over.
2. hula hoop the hips to show that the hips are free to move and aren't locked down without being pushed over.
3. lift either foot freely, one after the other, while not being pushed over.
4. able to step forward into the push without losing alignment or structure *and* without leaning into the push.
5. stay upright and not lean forward if uke suddenly disconnects.
These are just the basics of structure. The better your structure, the better you will be at handling force/energy/loads.
How to spot if you are cheating:
1. If you lean and shift your weight onto the right foot, you aren't structurally sound. It just means that instead of the left foot being pinned, you just replaced it with the right foot and right side being pinned. The spine should stay in the middle of both feet.
2. If your upper body sways while you hula hoop your hips. Especially if your shoulder area gets pushed backwards from the incoming energy. Any instability in the upper body shows a lack of structure.
3. As #2, if your upper body gets pushed backwards as you alternate lifting the feet, then you're not structurally sound. And as #1, if you sway to load the other foot, then you're not structurally sound.
4. If you lean into uke, you're not structurally sound. You're more than likely using your body as a lever to push off of the legs and into uke. Keep the body upright and straight.
5. If you lean when uke suddenly disconnects, it means you were using muscle or leverage to push into uke.
For more exercises like this, see my vid of the push test to the head:
Please note that I do lean. Yep, not the greatest of structure. But, notice that I don't lean into uke as he disconnects (#5). So, it's not horrible, just not the best it should be.
If we can agree that exercises like these show good structure and if we can replicate these exercises, then it's a step toward how I define aiki. Without structure, there can be no aiki. Then we can move on to intent, which is harder to show on video, let alone spirals. How we get there with video, I don't yet have a clue.