Just thought I'd add this little bit of info.
O-Sensei: In aikido, there is absolutely no attack. To attack means that the spirit has already lost. We adhere to the principle of absolute non-resistance, that is to say, we do not oppose the attacker. Thus, there is no opponent in aikido.
Hmmm ... seems to me that Ueshiba could very well be talking about Internal Arts. It certainly does fit the concept of what I know about them so far. It's all about internal centering without relying on outside sources, it's about not really doing anything to uke so yeah that's absolutely no attack and it really is non resistance because you aren't doing anything to build any type of resistance.
Things that make you go hmmmm ...