"What" is an Epit: Mathematical Foundations of Epistemic Structure

We introduce the epistemic unit (epit), a minimal formal structure for representing units of knowledge. Five axioms (EP1-EP5) define the epit as a tuple E =: an ordered triad, a relation triple in -1, 0, +1³, and an iso-type tau = iso (R1, R2, R3) in 0,. . . , 6. This tuple is the unique minimal structure satisfying all five axioms (Theorem 1. 2). The 27 relation triples partition under S3 into 7 iso-types (Proposition 2. 2). From 20 pure concepts on a 4-simplex of five epistemic axes, the framework generates 536 depth-0 epits (Proposition 2. 7). A constructor F: E³ x Tour3 -> E produces a countably infinite, well-ordered space (Theorem 3. 1) with growth Nₙ <= 1668^ (3ⁿ) (Proposition 3. 6). A Gödel limit epit dalet₀, well-formed but undecidable, establishes necessary incompleteness (Proposition 4. 4). The axiom system is satisfiable, independent, non-trivial, and relatively consistent with respect to ZFC (Proposition 5. 1).