Chris Parker
Grandmaster
For us, though, it comes (at least in part) from the spiritual teachings of the Kukishin traditions. In those, it's taught that the index finger, as the extension of the limb holding the weapon, is pointed to direct the Ki. This, from what I understand, is similar to some of the concepts in Hapkido and the way they work as well. In contrast, the Hakuun-related systems (Gyokko, Koto, Togakure) focus the Ki through the thumbs, with many kamae pointing them towards the heavens, created a connection between earth (where you are standing), man (yourself in kamae) and heaven (where the ki is directed - Ten Chi Jin.....).
Out of interest, Bruno, you start with the finger pointing, and then curl it in? A lot of swordsmanship I've gone through actually does the opposite, with the finger being pointed more through the cut, as that tightens the last few fingers, giving you a stronger, tighter grip as you impact the target, forming an integral part of te no uchi. I've heard it said that if you point the finger as you cut, it's impossible to lose your grip on the weapon. That said, Bojutsu tends to start with the finger pointed, although it seems to be kept out throughout the action of striking, in order to again get the proper mechanics for striking (in your grip).
Out of interest, Bruno, you start with the finger pointing, and then curl it in? A lot of swordsmanship I've gone through actually does the opposite, with the finger being pointed more through the cut, as that tightens the last few fingers, giving you a stronger, tighter grip as you impact the target, forming an integral part of te no uchi. I've heard it said that if you point the finger as you cut, it's impossible to lose your grip on the weapon. That said, Bojutsu tends to start with the finger pointed, although it seems to be kept out throughout the action of striking, in order to again get the proper mechanics for striking (in your grip).