The meaning of the word ‘PERTHRO‘ is unknown to the scholars, as it seems to have no other origin outside the runes. Rather than suppose that the word is lost, I treat this as intentional, as I must with all the names and their positions in the Aetts. Therefor, the reason that Perthro is unknown is because of all the runes it represents the unknown: Fate, the unmanifest, the unknowable and the nature of chance. Together all of these suggests Wyrd (the manipulation of chance and fate).
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A Note on Using the ‘Blank Rune’
The rune meaning of Perthro includes Wyrd, Fate, the mysteries of the unknown and unknowable. Most agree that it represents a ‘lot-cup’. It is the rune of the runes. Because this is so, we can immediately see why a ‘blank rune’ is an unnecessary addition to the 24 elder futhark runes. Typically, the ‘blank rune’ represents exactly those things that can be discovered and explored through Perthro — adding a blank rune into the strictly ordered futhark is at best redundant, and at worst a confusing impediment to genuine understanding (at least in the context of the system described by Rune Secrets.)
