Ratified by Shay 2026-07-24. Default flipped False -> True.
Evidence at ratification:
- 25 shape-bands, each holding SERVE at 720/720 wrong=0 on the SHA-sealed
ratified ledger (theta_SERVE=0.99, n >= 657 committed per band);
- deduction-serve lane 166/166 wrong=0 across six hand-authored splits;
- commit gate narrow by construction — a sentence-initial "therefore" IS an
argument, so the composer cannot claim turns that are not one;
- an unearned shape is still served DISCLOSED, never asserted.
Blast radius verified, not assumed: core test --suite deductive 268 passed
with the flag ON by default; a live default-config ChatRuntime decides real
English and existential arguments through grounding_source="deduction" while
ordinary turns still fall through to pack grounding; lane pins 10/11 match —
unchanged by the flip (the single miss is the pre-existing public_demo drift
documented for Tier S).
Rollback is flipping this back: flag-off remains byte-identical to pre-arc
dispatch and leaves no residue, pinned by
test_flag_off_preserves_pack_token_gloss_byte_identity.
curriculum_serving_enabled stays OFF — every curriculum band is unearned, and
the Sonnet brief now records the explicit bar for revisiting it.
Completes the all/no/some square. `some` is read for the first time:
"All mammals are vertebrates. Some whales are mammals. Therefore some
whales are vertebrates." is decided entailed; "All unicorns are horned.
Therefore some unicorns are horned." is decided unsettled, with the
no-existential-import reading disclosed in the surface.
Mechanism (generate/proof_chain/exist.py): v5-VP's per-individual
lowering over a domain widened by one Skolem witness per existential
premise and — the load-bearing part — one ARBITRARY element per
existential conclusion, at which every universal still instantiates and
about which no premise asserts anything. Refuting an existential means
deriving a universal, and the arbitrary element is what makes that
derivation genuine instead of an assumption of domain closure: without
it "Rex is a wolf. Rex is not tame. Therefore some wolves are tame."
reads as REFUTED from a domain of one wolf. With it, UNKNOWN.
Four `en_exist_*` bands earned SERVE at 720x wrong=0 on the first arena
seal (25-band ledger); the 32-case hand-authored v2_exist split passed
32/32 first run; full lane 166/166 wrong=0 across six splits.
Also fixes a wrong-answer path this work uncovered in Band v1b
(ADR-0261 §5.1): `to_syllogism` FILTERED premises it could not express
out of the projection and answered from the remainder, so "Aristotle is
a philosopher. All philosophers are scholars. Therefore some scholars
are philosophers." lost its only witness and was served "that doesn't
follow". It now refuses — matching its propositional sibling
`to_deductive_logic`, which always has — and the argument falls through
to the bands that can hold a singular fact. The categorical band
re-earned SERVE 720/720 after the change; both examples are pinned as
regression cases.
Promotion: `ds-mem-0020` declined -> unknown (ADR-0258's existential
scope-out, now read; an anonymous witness never transfers to a named
individual, so UNKNOWN is its honest verdict, not entailed).
[Verification]: core test --suite deductive 232 passed; reader tests
33/33; register+surface tests 52 passed; arena 25 bands x 720 wrong=0
(all SERVE); lane 166/166 wrong=0; lane SHAs 9/10 match (public_demo
drift is pre-existing on the base commit and unrelated — evidence in
the Tier-S brief).
Generalization arc Phase 1.1 (Tier F, docs/plans/generalization-arc-2026-07-24.md):
"All philosophers teach. Socrates is a philosopher. Therefore Socrates
teaches." now reads and decides — the ADR-0258 §6.3 verb-predicate
scope-out, and the reading gate for Phase 2's subject serving.
generate/proof_chain/verb.py extends v3-MEM's per-individual lowering with
a second atom family in one shared space: membership atoms (v3-MEM's own
parsers reused verbatim) + verb atoms (individual, verb-lemma-group,
object-term). Verb universals instantiate as mem(i,C) -> [~]verb(i), so a
copula-minted membership fact discharges a verb rule. The ONE new semantic
identification is closed 3sg agreement (verb-specific irregular table +
the three regular suffix rules — deliberately NOT the noun table, which
would misroute "lives"/"leaves"). Scope-tight segmentation: single-token
name/class/verb/object shapes only; everything longer refuses typed
(tense_out_of_band joins the closed reason vocabulary). Rendered by
render_entailment_verb (member surface, UNKNOWN scoping extended to the
verb reading). Rides deduction_serving_enabled (default off); pure
widening — every previously-served argument byte-identical, no existing
lane case changed outcome.
Earned: 4 en_verb_* bands x 720 arena wrong=0 (first seal), ledger resealed
at 21 bands; corpus soundness asserted against the independent truth-table
oracle over each template's intended lowering (15,120 cases, INV-25).
Lane: v2_verb 28 hand-authored real cases 28/28 first run; full lane
134/134 wrong=0 across five splits. Surgical single-line pin update +
CLAIMS regen.
Stacked on feat/generalization-phase0 (merge that first — shared
verify_lane_shas.py / CLAIMS.md / generate_claims.py lane-ADR mapping).
[Verification]: verb reader tests 34/34; deduction battery 86/86
(surface +5, e2e +1, lane +1) in-worktree; arena seal + oracle
cross-check green; smoke + warmed_session via pre-push gate.
Composes v2-EN's connective grammar (if/then, or, and, either) with
v3-MEM's singular-membership sentence reading over one shared
per-individual atom space, so "If Socrates is a man then Socrates is
mortal. Socrates is a man. Therefore Socrates is mortal." decides — the
exact gap ADR-0258 §6.1 reserved. Genuinely fuses the two mechanisms: a
bare universal's instantiated atom can unify (via the same closed
morphology relation) with a connective leaf's atom, deciding arguments
neither band alone could.
- generate/proof_chain/cond_member.py: new reader. A sentence is checked
for a connective token BEFORE the universal-lead check (so a stray
connective can never leak into an opaque name/class run); reuses v3-MEM's
own _parse_singular/_parse_universal verbatim (already negation-aware,
so no separate negation layer is needed, unlike v2-EN's opaque minter).
Four new shape-bands (fused/disjunctive/chain/conditional), each earning
its own SERVE license.
- chat/deduction_surface.py: new fallback tier tried strictly after v3-MEM
— pure widening, every previously-served argument stays byte-identical.
- evals/deduction_serve/practice/gold.py: 4 new synthetic template groups
(20 templates), reusing the v3-MEM case generator; intended formulas
cross-checked against the independent oracle (INV-25).
- evals/deduction_serve/v2_condmem/: 26 hand-authored real-English cases,
content-disjoint from the synthetic corpus.
- ds-mem-0024 promoted declined -> unknown (not entailed — the antecedent
is never asserted in that text; this is the first promotion in the
corpus that doesn't land on entailed).
- Ledger re-sealed to 17 bands; deduction_serve_v1 lane SHA re-pinned
(surgical single-line edit, not a blanket --update).
Verification: core test --suite deductive 160 passed (31 new reader
tests); practice arena 17 bands x 720 wrong=0, all SERVE-licensed; lane
splits v1 28/28, v2_en 26/26, v2_member 26/26, v2_condmem 26/26; smoke 180
passed; warmed_session 10 passed. Flag deduction_serving_enabled stays
default-off.
CORE now decides natural-English deductive arguments end-to-end:
'If it rains then the ground is wet. It rains. Therefore the ground
is wet.' -> ENTAILED, rendered over the user's own clauses. Both of
ADR-0256's documented boundary cases (multiword conditional, nested-
negation contraposition) are now decided; their lane gold updated
declined->entailed.
- generate/proof_chain/english.py (new): closed function-word grammar
over OPAQUE clause-atoms (minted ids); if/then, [either] or, and,
three negation forms (leading not / sentential / copular incl.
contractions); typed refusals; honesty caps. Soundness: positive
verdicts are substitution-closed; UNKNOWN is scoped + guarded
(quantifier-led, is-a membership, unnormalizable negation refuse
out of the opaque band).
- render_entailment_english: verdicts quoted back verbatim; UNKNOWN
phrasing explicitly scoped to the opaque reading.
- chat/deduction_surface.py: v2-EN fallback tier AFTER v1/v1b —
monotone widening, byte-identical on previously-served arguments.
- Four en_* shape-bands EARN SERVE via the ADR-0199 arena (720/band,
wrong=0, reliability 0.99087 >= 0.99); 9-band ledger re-sealed.
- evals/deduction_serve/v2_en: 26 hand-authored real-English cases
(content disjoint from the synthetic lexicon), wrong=0; report
re-pinned.
- realizer guard (ADR-0075): deduction surfaces exempt — quoted
templates are not slot-composed articulations (pack 'open'=VERB
was rejecting an honest quoted 'the door is not open'); pinned
cold+warm in e2e.
[Verification]: deductive 84 passed; smoke 180 passed; cognition 122
passed 1 skipped; arena 9x720 wrong=0 all SERVE; lanes v1 28/28,
v2_en 26/26.
core chat now decides Aristotelian syllogisms end-to-end -- the marquee
'basic logical work' widening. Closes Phase 0's fork: the ONLY categorical
decider was evals/syllogism/oracle.py (the sealed independence oracle serving
must not import; INV-25). This ships a production decider.
generate/proof_chain/categorical.py lowers a categorical argument to the
propositional regime (one Boolean atom per term-membership profile) and rides
the already-verified ROBDD engine -- no new decision procedure, soundness
inherits from the flagship. Sound AND complete for the modern/Boolean reading
(Darapti + existential-import-only forms correctly INVALID), with no reliance
on a lucky domain size. Independent of the eval oracle by mechanism (ROBDD-
over-profiles vs brute-force finite-model enumeration); proven by case-for-case
agreement with it across the whole syllogism gold lane.
New: generate/proof_chain/categorical.py, render_syllogism (deterministic
valid/invalid/inconsistent templates), CATEGORICAL shape-band, arena
categorical band (4 valid forms + 2 invalid, by-construction gold cross-checked
vs the independent syllogism oracle), tests/test_categorical_decider.py (8
tests incl. the independence-by-agreement proof).
Changed: chat/deduction_surface.py (categorical branch, license-gated via a
shared _license_gate helper; propositional path byte-identical), arena
DeductionSolver dual-path in lock-step with the composer, re-sealed ledger (5
bands, categorical earns SERVE at 0.99087 wrong=0), Phase-2 lane decide()
mirrors the dual path with the 3 categorical cases reclassified to their true
valid/invalid verdicts + 1 invalid case (n 27->28), report+SHA regenerated.
Honest wrinkles: irregular plurals ('fish') decline with unknown_morphology
(a reader limit, correctly not a wrong); surfaces read in singularized terms
('all whale are animal') -- the exact ids the engine reasoned over, no cosmetic
re-pluralization that could drift from the decision.
[Verification]: smoke 180 passed; cognition 122 passed/1 skipped; core test
--suite deductive 45 passed; test_categorical_decider 8 passed; practice
runner 5 bands all SERVE wrong=0; deduction_serve lane SHA regenerates to the
committed pin.
Wires the verified ROBDD entailment engine (generate/proof_chain,
716/716 wrong=0) into core chat serving. A propositional argument
('P1. P2. ... Therefore C.') is now comprehended, projected, and
decided end-to-end -- the first real working basic-logic workflow:
user question -> CORE decides -> articulated deterministic answer.
New: chat/deduction_surface.py (DEDUCTION composer, sibling to the
existing oov/narrative/example composer pattern), generate/proof_chain/
render.py (deterministic EntailmentTrace -> surface templates, no LLM),
tests/test_deduction_surface.py (15 tests incl. full propositional gold
corpus decided end-to-end across a multi-turn session, wrong=0).
Changed: core/config.py (deduction_serving_enabled flag, default off),
generate/intent.py (IntentTag.DEDUCTION, observability-only -- the core
classify_intent rule table is untouched so flag-off stays byte-identical),
chat/runtime.py (one flag-gated block in the existing pack/teaching/
partial/oov dispatcher).
Design notes (full detail in docs/research/deduction-serve-arc-phase1-
turn-spine-2026-07-23.md): the deduction check runs BEFORE generic intent
classification (never touches classify_intent's rule table) and BEFORE
the empty-vault gate (a live multi-turn probe caught turn-12 silently
falling through once the vault warmed -- pack/teaching/oov are cold-start-
only by design, deduction serving isn't). grounding_source='deduction' is
NOT registered in the closed, Workbench-coupled GroundingSource Literal
(cross-stack TS contract, inert for this arc's core-chat-only consumer,
documented as a deferred follow-up). Band v1 stays propositional-only --
categorical/syllogism arguments commit but honestly decline as
out-of-band; evals.syllogism.oracle is never imported (INV-25 intact).
[Verification]: smoke 180 passed; cognition 122 passed/1 skipped;
test_deduction_surface.py 15 passed; test_dispatch_trace.py +
test_oov_surface.py 26 passed; test_intent*.py 145 passed.
