There are threads here on Aikiweb that deal with the meaning of circle, triangle, and square. I was more interested in the origination of them by Ueshiba.
All very well and good, better (in most cases) to have more information to sort through than less. Still, I think Mark is looking for evidence of "the origination of them (
) by Ueshiba." In other words, does anyone have direct evidence
that Ueshiba drew from a specific source for his particular paradigm or direct evidence of his particular paradigm being unique unto him (and at what time), or a combination of both.
I am sure that you are aware that Triangle Circle Square stuff is not rare in Japan and isn't particularly rare outside of Japan even when one limits oneself to schools of Martial Arts specifically. Therefore, if one wishes to attribute meaning specifically originating from an individual, one had best be careful, or one will be subject to criticism for painting with an extremely broad brush. I'm guessing that Mark is trying to be careful. Hence the narrow question.
For example, if one were to research the variety of Omoto-kyo interpretations of these symbols that alone would not provide direct evidence that that was the primary source of Ueshiba's understanding, although it might very well help to narrow the field.
Ueshiba's own writing, of which I believe there is plenty, would be a good place to start looking. It is my understanding that the Ueshiba family is in possession of a significant store of this. I suppose if they thought it important to the future of Aikido, an effort would be made to have this material made public . . .
. . . just as one entrusts the future of one's training unquestioningly to one's sensei, so must we all trust that all that needs to be revealed/taught, has been revealed/taught, is being revealed/taught, and will be revealed/taught, when (and to whom) it is best . . . for Aikido. (Isn't that right Peter?)
p.s. George, I love you man, but when are you going to learn to stop this whole cowboy questioning thing, shut up and be assimilated? How can you expect to become "one with the universe when you keep standing on the outside asking, "What is the universe?"
p.p.s. Mark, Why do you want to know?
p.p.p.s. Bob, It's the patches. Forget the belts, forget the certificates, the adulation, respect, etc. It's all about the patches! BTW, that's the problem with Buddhism today . . . NO PATCHES!