distinction_forces_T0
plain-language theorem explainer
Any type carrying two distinct points forces the T0 recognition-work surface on the observable quotient generated by that distinction. Foundation workers cite it as the Phase-1 bridge from a raw inequality witness to the early forcing spine. The proof assembles the T0 structure by transporting the Boolean recognition cost across the forced quotient–Bool equivalence and discharging each field with the transported cost axioms.
Claim. Let $K$ be any type and suppose $h$ asserts that there exist $x,y\in K$ with $x\neq y$. Then the forced observable quotient of $h$ carries a T0 recognition-work surface: it is Boolean, admits a recognition-work cost constraint, the empty/consistent state has zero cost, every inconsistent configuration has positive cost, cost obeys the dichotomy axiom, and cost is additive on independent joins.
background
This module opens the closure path from a supplied distinction witness to the early forcing spine (Phase 1 of T−1→T8). Given $h:\exists x,y:K,,x\neq y$, the upstream construction TMinus1ForcedFromDistinction builds the forced observable quotient and proves it equivalent to Bool. The point is to thread T0 through that distinction-generated floor rather than through unthreaded global Boolean facts.
A cost function on a configuration space is a nonnegative map $C$ satisfying dichotomy (zero cost iff the configuration is consistent) and independent additivity (cost adds over joins of configurations that share no predicates). The lemma cost_pos_iff_inconsistent restates dichotomy as positivity of cost exactly on inconsistent states.
Here the configuration space is the forced quotient of $h$, equipped with the transported recognition cost obtained by pulling back the Boolean T−1→T0 cost along the forced quotient–Bool equivalence. The structure T0_FromDistinction packages the Boolean character of that quotient together with the full recognition-work surface on it.
proof idea
Tactic-mode construction of the five remaining fields of T0_FromDistinction (the Boolean equivalence is supplied as a witness in the signature).
recognition_workis the preexisting certificateforcedQuotient_recognition_work_constraint h.consistency_cheaprewrites via the transport identityforcedQuotientRecognitionCost_transport, simplifies through the Bool equivalence, and closes by reflexivity (empty Bool config has zero cost).contradiction_expensiveappliesCostFunction.cost_pos_iff_inconsistentto the transported cost, converting inconsistency of $\Gamma$ into positive cost.logic_emergentis the dichotomy axiom offorcedQuotientRecognitionCost h.additive_indepis the additivity axiom of the same transported cost, applied to independent pairs.
why it matters
This is the first concrete forcing step from a raw distinction to the Recognition spine: T0 on the quotient the distinction itself generates. Downstream, distinction_forces_T1 is a one-line lift of this result, and distinction_forces_T3 chains it with the T2 step. The spine package distinction_forces_T0_spine records the Boolean quotient witness among the T−1-to-T4 data forced by any distinction.
In the broader framework this anchors Phase 1 of the T−1→T8 closure: once T0 sits on the distinction-generated floor, later steps (J-uniqueness at T5, $\varphi$ at T6, the eight-tick octave at T7, $D=3$ at T8) can be routed through transported structure rather than global Bool facts. It does not yet force those later landmarks; it only installs the recognition-work surface that the rest of the chain rides on.
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