Russell Staandish wrote > Equivalence in the sense of category theory's notion of duality. In > Venn diagrams, for instance, the empty set is the dual of the > universal set.

> More particularly to the "bitstring ensemble" ASKA "Schmidhuber > ensemble"* or UD*, the empty observer moment can be identified > with Nothing, and the empty observer moment is the whole plenitude. > Of course the flip side to "can be" is "can't be" - but in that case, > I'm afraid, Nothing does not seem to be a well defined concept (I > stand to be corrected of course!). Interesting, I'll bear it in mind, along with Bruno's comments.