Here is where the mention of it started:
http://rumsoakedfist.org/viewtopic.php?f=3&t=5791
In the link provided, http://www.taoistinstitute.com/pdfs/Legacy-of-Haumea-Lefiti.pdf, there was a paragraph about the square, circle, and triangle.
Part of the characteristics of Mok ga was the use of practical concepts from math, especially geometry. Tiny explained that if one truly understood the functional use of the square, circle, and triangle in combat, they would become a highly skilled fighter.
The founder of aikido, Ueshiba, mentions the square, circle, and triangle. So I posted on Aikiweb, asking if anyone knew how these two concepts from Mok ga and aikido were related. I received some answers on how Ueshiba viewed the concept, but no posts on if the two systems had similar or separate views.
The Aikiweb thread is here: http://www.aikiweb.com/forums/showthread.php?t=16645
My questions for those here are
Does anyone know how these two concepts are related? Ueshiba seemed to view this concept both martially and spiritually. Does anyone know if both of those are similar to how Mok ga views the square, circle, and triangle? What other systems use this concept, either martially or spiritually?
Thanks,
Mark