Okay....very simplistically.....it seems that at the extreme ends of nested systems (i.e. subatomic particles and cosmology) science is in the realm of conjecture based on mathematical speculation. We can now go at least 3 ways,
1. There is no limit to mathematical speculative models and the nesting could remain infinitely "open".
2. Mathematics is a product of "consciousness" as is "all reality" and consciousness may or not be "bounded". (an esoteric conclusion)
3. "Reality" whether it be contingent on mathematics or consciousness or otherwise is in the gift of "an absolute deity" thereby providing ultimate closure. (a theistic conclusion)
Von Foerster leaves the question of "closure" open (
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) but some of his acolytes (e.g. Bernard Scott) are leaning towards theism in a move which brings to mind Bishop Berekeley's requirement for "God" as an "ultimate observer".