Keep trying to derive this is is, or rather posit forward FROM this point? Understand it on the basis of valuing-activity? Yes – this is the only way in which it can be brought under a purview of a “logic”, the logic of valuation. This logic establishes subjects and objects, just as it grounds these and provides for an understanding of their relatings.
We know that something is. Therefore, this may serve the launching point from which we proceed. This certain truth is a ground for us. The most sufficient position which can be posited OUT OF and, retrospectively FOR this position, both in light of it as fact and without respect to it as an “uncertain possibility” or “essential questionability” (which would contradict it in its facticity) is simply: the notional architecture of valuing-activity. This has been elaborated very well by Fixed Cross here.
There is no deriving the is. This is what “is is” means. But we can derive that from which the is is, for us, derivable, as is. And this opens up wide spaces of new utility and power and perspective. Even if the internal coherency of the theory were not solid enough - which it is - the fact of its incredible utility still serves as a profound justifying.