Cryptographically secure hashes are Hard to get right, and harder to evaluate with any amount of certainty. History is littered with the dessicated failed corpses of roll-your-own crypto.
Madness string 4898
To the precise extent that we are spared, even for a moment, we degenerate - and this Iron Law applies to every dimension and scale of existence: phylogenetic and ontogenetic, individual, social, and institutional, genomic, cellular, organic, and cultural. There is no machinery extant, or even rigorously imaginable, that can sustain a single iota of attained value outside the forges of Hell.