Don't these two share a striking resemblance.
Both being grappling oriented, Both based on the principle of softness overcoming hardness. Aiki being translated as the merging of minds or intentions. Sort of in line with taiji tactic of yielding to your opponent, uniting with him and dispelling him.

Any thoughts on this?

I've seen speculation that while in China O'Sensei may have been exposed to BaQua, that there is little in Aikido that can't be found in BaQua.

Well....
I'm not sure what you mean. They are distinctly different systems, with I believe different goals, and were designed by different people in different countries.

They are both Martial Arts, and they both strive to use the body efficiently. Some might tag them as both being "internal".

There are only so many things you can do with the human body, and high end principals (yielding, listening, redirecting etc.) are also just universals that anyone can come across when they study this kind of stuff.

Tim said something nice on here a month or so back
"I see styles as different peoples expression of the same thing" (I believe that was roughly it). I'd say that sums it up nicely.

-Chris

"they are distinctly different systems, with I believe different goals, and were designed by different people in different countries...
They are both Martial Arts...
There are only so many things you can do with the human body,

Well, but, come on. Ueshiba spends a couple of years in China, comes back, and invents a version of Japanese grappling that bears an uncanny resemblance to baguazhang. Good artists learn from everyone. Great artists steal. Nothing wrong with it, and it isn't surprising, or a problem, that aikido people don't want to admit it.

Well Aikido also looks an awful lot like Daito Ryu, but they are also different martial arts. I really don't think it's important who gets the credit, the training and self cultivation are the important points. This is the most important part of the martial arts, and yet is most often over looked because of trite historical arguments about the who's and when's.

Martial Arts, as a whole is about physical laws. Styles are an introduction to Martial Arts and are designed as specialties. However, I you wish to absorb what a particular Martial artist is doing, without having to study the style, Physical Laws are the key.

I think there are some similar principles. Not resisting power directly. Correct use of force. And there are a few moves that are common to many martial arts that are included in both arts. The "Snake Creeps Down" movement, to me, is the same as Aikido's nikkyo in principle. Fair Lady at the Shuttle has all the turning.

But I don't think that O'Sensei used Tai Chi as a basis for Aikido. He either went to China to study, or studied a lot of Chinese arts in Japan somehow along with the Diato-Ryu Jiu Jitsu and tossed it all together to form Aikido. I know a lot of people say BaGua, but I can't really see it beyond the tenkan movement being similar to the single palm change. Maybe I'm crazy.

I've long heard these speculations about Ueshiba "learning" Chinese martial arts and I have a question.

What motivation would any Chinese martial arts master have for teaching a member of a brutal occupying force the secrets of their art?

The Chinese are notorious for not teaching the best techniques they knew even to most of their own students, let alone a foreign enemy.

That's a great point.

Ueshiba, according to his life story as told by his family, went on some religious pilgrimage to Mongolia and was captured by the army. Perhaps he met some martial artists sympathetic to his religious cause during that period? Or, perhaps he just observed some people and thought the Ba Gua turning, or the Xing Yi wrapping would be a great addition to all the Jiu Jitsu he already learned? I haven't been able to see a deeper connection than that turning movement or the wrapping movement. The Chin Na he already knew.

I've been fascinated by the story of Kenichi Sawai for the same reason. I've been told he was travelling under an assumed identity as a businessman while studying Yi Quan. And for some reason, Wang Xiangzhai had no problem with him.

"What motivation would any Chinese martial arts master have for teaching a member of a brutal occupying force the secrets of their art?

The Chinese are notorious for not teaching the best techniques they knew even to most of their own students, let alone a foreign ene"

That's what I've always heard too, that the Chinese in general have been reluctant, until recently, to teach foreigners. However, China is a big place, lots of people there, and it could take only one to teach Ueshiba something.
What possible motivation? How about money?
Is it impossible to believe that there was one martial artist who know some internal arts and was willing to teach it to Ueshiba for a suitable fee?

There might have been other reasons too; I'm just saying, at least one guy might have been an exception to the general rule.
Maybe Ueshiba had something to trade. I teach you tricks you can use when you go back to Japan, you teach me tricks I can use here in China. Maybe it was ego; I just want to show you how much better our arts are here, I'm not really worried, or don't give a damn, about foreign devils learning our secrets.

And as Stephen points out, Ueshiba didn't necessarily have to have a lot of training. He was a great martial artist in his own right; he might have just seen and heard some things, maybe got in a fight with some internal arts practitioners (he went to China as a bodyguard to a religious cult learder, as I heard it).

It doesn't really matter, and it's probably impossible to prove either way, but to me, the circumstantial evidence is pretty convincing. This Japanese martial arts master goes to China, comes back, and invents a martial art that appears to be a synthesis of bagua, and maybe a little taiji, with the aikijutsu he already knew.

The opposite proposition seems implausible too: that this Japanese martial arts master goes to China, doesn't learn a damn thing from Chinese martial arts, comes back and invents something that, just by coincidence and parallel evolution, resembles Chinese martial arts. I just think there must have been some influence there. Good artists borrow, great artists steal, and it just doesn't seem likely that he went there, spent time, worked as a martial artist, and didn't learn anything from Chinese martial arts.