Thanks for the links. I have some of Yang Jwing-Ming's books on taiji, and I think he explains some of the same concepts there. I think this lecture had some additional information that I hadn't seen explicitly before, so it was interesting. In particular, I don't remember his books having any of the equations he used towards the end of the lecture. Thanks, hopefully others will find it interesting, too.
oh yeah, I love his explaination,
his interpretation is really good. I watch the whole thing in one shot, I hope there are more. the concept of qi is familiar to me but it's also not. kind of complicated i guess. I will have class next semester so will further more discuss in this topic.