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IndisputableMonolith.Foundation.BooleanProjectionFromMark

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Defines a marked two-point pair on a carrier and the induced map to Booleans. With a named mark the projection is canonical; without it, no canonical Boolean structure exists. Foundation material for forcing T−1 from a bare distinction witness. Argument is definitional plus short uniqueness/non-canonicity lemmas and a certificate bundle.

claimA marked pair is a carrier $X$ with a named two-point subset $\{a,b\}\subseteq X$, $a\neq b$. From such a mark one obtains a canonical projection $X\to\{0,1\}$ sending the two marked points to the two Boolean values. Absent a mark, no canonical Boolean projection on $X$ is forced.

background

Recognition Science begins the forcing chain below T0 by treating distinction, not an external admissibility package, as primitive. This module supplies the minimal combinatorial gadget for that step: a named two-point mark inside an arbitrary carrier.

A marked pair packages a type together with two distinguished, unequal elements. The Boolean projection sends those two points to the two values of $\mathrm{Bool}$ (or ${0,1}$) and thereby induces a two-valued labeling. The companion statements record that the projection is unique once the mark is fixed, and that without a mark there is no canonical choice of Boolean structure on the carrier.

The module sits in Foundation and is imported by the T−1 repair that rebuilds the first forcing step from a distinction witness alone.

proof idea

Definition module with thin lemmas. MarkedPair is a structure (carrier plus two named unequal points). boolProjection is the induced map to Bool. Canonicity given a mark is a short uniqueness argument; non-canonicity without a mark is a counterexample-style non-existence claim. BooleanProjectionFromMarkCert packages the definitions and lemmas for downstream import. No deep tactic proof; the content is the interface.

why it matters in Recognition Science

Feeds IndisputableMonolith.Foundation.TMinus1ForcedFromDistinction, the non-half-measure T−1 repair whose primitive is a distinction witness rather than an external admissibility package. By isolating Boolean projection as something that appears only after a named two-point mark, the module makes precise how a bare distinction yields a two-valued structure and nothing more. That is the combinatorial seed for the rest of the forcing chain (T0 onward) without smuggling classical Boolean assumptions into the foundation.

scope and limits

used by (1)

From the project-wide theorem graph. These declarations reference this one in their body.

declarations in this module (6)