What About One Uncuttable Atom?
While atomists such as Democritus posited that the universe was made up of numerous uncuttable atoms, the Platonists painted a very different picture of the world. Instead of viewing the Universe as a collection of pieces or parts, the Platonists began with the concept of an Overarching Whole, or Absolute form of Unity.
Starting with an All-Encompassing Everything gives rise to a model of the Universe with some very unusual properties. First and foremost, starting with an Overarching Whole gives rise to a Universe that is inherently boundless and limitless, making it truly Infinite in nature. Since there is nothing that lies outside of this inherent Oneness, it has no bounds or limits.
Rather than arising "out of" this homogenous Whole, all particular things must necessarily arise within the purview of the All-Encompassing Everything. And this is where things start to get really weird. No matter how many particular "things" are sectioned within this Overarching Whole, this Absolute form of Unity retains its limitless nature.
When viewed in this light, this All-Encompassing Everything has the properties of a limitless Uncuttable Atom — further illustrating just how divergent the Platonic perspective and the atomistic model are from one another.
Starting with an All-Encompassing Everything gives rise to a model of the Universe that has the properties of both open and closed systems. Under this model, the Universe is "One Thing", indicating that it is inherently discrete and therefore can be treated as a closed system. However, this "One Thing" is also inherently limitless and boundless, imbuing it with characteristics of an open system as well.
Which is it?
Under this model, the Universe is simultaneously both — and neither — intimating that Reality that can never be completely captured or described through language.