It's been a while - but IIRC, The Tao Is Silent is Taoism for nerds. I encountered Taoism via the martial arts - and TTIS skips over most of the bits of Taoism I find interesting, and goes straight for the bits Raymond Smullian liked - i.e. all the nerdy bits. As I recall, my reaction was something like: yes, this is all very amusing - but heaven help anyone who is learning about Taoism from Smullian.