How can you talk about non-being without turning it into a something?

Every morning I practise taiji in the park and every evening I read a few lines of the Laozi with my grandson's dictionary. Chapter 40 says, roughly, that the things of the world are born from being, and being is born from non-being. Wang Bi, the commentator who died in his early twenties and still wrote the commentary everyone reads, made this central: non-being (wu) is the root, and being is what grows from it.

My difficulty is old-fashioned. As soon as I say "non-being is the root", I have made non-being into a thing that does something, which is exactly what it was supposed not to be. Parmenides apparently warned against this two and a half thousand years ago: do not say or think what is not. And Heidegger, I am told, opened a lecture course by asking why there are beings at all rather than nothing, then spent a long time arguing about whether "the nothing" can be spoken of.

So here is my question, and I would welcome several answers that disagree:

• Is Wang Bi's wu really nothing at all, or is it a name for something without determinate qualities, which would make it a kind of being after all?
• Is the Parmenidean objection fair to the Daoists, or does it assume a Greek grammar of "is" that classical Chinese does not share?
• Or is the whole thing a matter of practice rather than theory, the way the empty centre of a wheel is useful without being a part of the wheel?

I spent forty years designing railway signalling, where a gap in the circuit is a very definite something. Perhaps that is my problem.