Tim Fong wrote:
..."kihon" before "taijutsu."...the conditioning exercises (or as Akuzawa calls it, tanren) create the "core" of the technique.
Yes, tanren is the "core" of all the Japanese martial arts. But there is also something centrally unique to each of them, as to how they variously use that core to achieve their own peculiar affects. What is the difference, then, in aikido and sumo or jujutsu, judo, etc.?
Mark mentioned that there is some discussion about whether aiki is based on kenjutsu, but I don't take that too problematically. The old "aiki no in-yo ho" go way, way back and were a consideration for sword fighters. How much of that actually carried through to Takeda's daito ryu may be in question, but avoidance of the sword has always been a major concern for aiki arts. Avoidance and taking. And Mochizuki Sensei went into a lot of detail about how various movements were taken directly from sword movements and how various techniques were based directly on sword techniques. He even had a kata called Ken Tai Iichi no Kata (forms of sword and body are one) to show the direct correlation. It is a point of consideration that his sword forms were all rooted in katori shinto ryu, while Ueshiba's and DTR's generally were based on Ona Ha Itto Ryu, but in his way of teaching the aiki-kenjutsu/taijutsu connection was central.
So my question remains, what, exactly, differentiates aikido from sumo/jujutsu/judo, since all are based on tanren, and how does the internal pressure model explain non-contact aiki?