[MD] Venn or Ziggurat

[Andre Broersen]

Frank, I tend to think of the stack as a cone of pyramid, then you get
the circular (or square) Venn diagram by looking down on it.
Ian  in response to Franf's:

I often hear of the "levels" as if stacked up like a ziggurat.
Wouldn't a Venn diagram with 4 concentric regions be truer to the concept of quality built of quality built of quality built of quality?

Andre:
Or the ZEN circle.