The Encyclopedia of Religion situates Sethian cosmology within late antiquity's wider intellectual world, not as an isolated biblical reinterpretation but as a system built partly from the vocabulary of Middle Platonist philosophy, which already distinguished a highest, unknowable first principle from a lesser craftsman figure, the demiurge of Plato's Timaeus, who shapes the material cosmos from pre-existing matter rather than creating it from nothing. Sethian writers took that philosophical structure, an ultimate transcendent source above a subordinate maker, and fused it with a negative reading of the biblical creator, so that Yaldabaoth carries both a philosophical genealogy, the demiurge figure familiar from Platonist cosmology, and a scriptural one, the jealous god of Genesis, at once. Karen King's study of the category argues that this fusion is one reason Gnostic cosmology proved so intellectually serious a rival within the wider late antique religious landscape: it was not simply asserting an alternative myth but arguing, using tools of philosophical argument educated readers of the period would recognise, that the god of conventional scripture could not coherently be the ultimate reality precisely because he acted, spoke and claimed exclusivity in ways a genuinely supreme, transcendent first principle by definition would not.