— by reason of indescribability; — for you (grammarians); — of it; — the (proper) nature; — is lost; — of one whose own nature is not discerned; — the status of being nescience; — how; — is established
By calling it indescribable, for you its very nature is lost; and of something whose own nature is undiscerned, how can the status 'nescience' be established at all?