Hylaean Theoric World: The name used by most adherents of Protism to denote the higher plane of existence populated by perfect geometric forms, theorems, and other pure ideas (cnoöns). Named after Hylaea, one of the two daughters of Cnous.

Stephenson creates difficulties by contrasting the Hylaean Theoric World (or Platonic Ideal) against the multi-cosmi as a product of the sum of probability choices. For instance, Stephenson implies, via the Wick argument, that somewhere there is a HTW full of pure ideas, and that the Arbran Causal Domain is a closer approximation of that HTW than other causal domains. Conversely, there must by extension be a more perfect Causal Domain that influences Arbre. From this one may speculate that there is a single ideal probability wave form.

1) However, if there are Terrible Events on Arbre, and apparently on Earth (possibly the apocalypse), than by extension there would seem to be terrible events in the Hylaean Theoric World, a notion which is possibly opposite the idea of perfection.

• counter argument: These events are extreme manifestations of aspects in which lesser perfect worlds differ from the HTW.

2) As Incanters are capable of manipulating wave forms, why do they not just alter events to match a perfect wave form/narrative?

• counter argument: A perfect narrative may disallow the existence of (human) beings and/or chance, free will or at least the possibility of gaining knowledge. (Because every knowledge is already present here.)

3) In order to explain communication across Cosmi, Stephenson posits a feedback loop with "attractors." This argues for a mechanistic universe, a teleological universe, which is generally frowned upon currently. ["Generally frowned upon currently" is a phrase that would be readily planed by an avout.]

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