# Experiment 60B.25 — Diagnosis: Proposition-Plus-Rationale Instead of Clean Question

**Branch:** `feature/question-family-specificity-v0.29`  
**Date:** 2026-08-13  
**Status:** COMPLETE  
**Type:** READ-ONLY DIAGNOSIS (no code changes)

## Objective

Answer one measurable question:

> Why does deterministic formulation preserve the whole proposition-plus-rationale string instead of converting the unresolved proposition into a concise interrogative question?

Input node (from 60B.24):
```
label: "Prospective enterprise customer signing status"
description: "Whether one prospective enterprise customer will sign if we launch this year; they account for ~£700k of the £1.2M expected annual revenue, so that resolving their intent is needed to assess the financial impact of launching now."
```

Produced question:
```
whether one prospective enterprise customer will sign if we launch this year; they account for ~£700k of the £1.2M expected annual revenue, so that resolving their intent is needed to assess the financial impact of launching now?
```

## Checkpoint 1 — Extraction Behaviour (full trace)

### `extractMeaning(node)` trace for the fixed node:

**Line 86:** `raw = "Prospective enterprise customer signing status Whether one prospective..."`

**Line 87-89:** `meaning = stripTrailingPunctuation("Prospective enterprise customer signing status")`
→ `"Prospective enterprise customer signing status"` (no trailing punctuation to strip)

**Line 92:** `hasAudienceIdentityQuestion(lowered)` → **NO**  
None of the patterns match: "who is the customer", "target customer", "identifying the customer", etc. The word "enterprise customer" does not match any pattern — it's a noun modifier, not an audience-identity construct.

**Line 96-97:** `strippedDescription = stripTrailingPunctuation(description)`
→ Full description text with no trailing punctuation change (it ends with period which gets stripped).

**Lines 102-108 — THE KEY BRANCH:**
```js
if (
    /\b(status|likelihood|probability|chance|risk|uncertainty)\b/i.test("Prospective enterprise customer signing status") && // MATCHES "status" ✓
    /^whether\s+/i.test(strippedDescription)  // MATCHES "Whether..." ✓
) {
    return sentenceCase(strippedDescription);  // ← ALL text returned
}
```

Both conditions match. **This branch is taken.**

`sentenceCase("Whether one prospective enterprise customer will sign if we launch this year; they account for ~£700k...")` →  
**lowercases first char, preserves everything else including rationale after semicolon**

### Checkpoint 1 Answers:

| Question | Answer |
|---|---|
| label considered? | **YES** — used to trigger the status regex |
| description considered? | **YES** — full text passed to sentenceCase on line 108 |
| returned meaning | `"whether one prospective enterprise customer will sign if we launch this year; they account for ~£700k of the £1.2M expected annual revenue, so that resolving their intent is needed to assess the financial impact of launching now."` (first char lowered) |
| rationale stripped? | **NO** — line 108 returns full `strippedDescription` |
| semicolon boundary recognized? | **NO** — no split logic exists for description extraction |
| "so that" rationale recognized? | **NO** — no rationale marker detection in extractMeaning |

## Checkpoint 2 — Interrogative Conversion (full trace)

### `isInterrogativeMeaning(meaning)` trace:

Input: `"whether one prospective enterprise customer will sign if we launch this year; they account for ~£700k..."`

- Line 170 (`wh-questions`): No match — starts with "whether", not who/what/where/when/how
- Lines 179-186 (aux inversion): No match — first word is "whether", not a modal auxiliary
- **Line 189: `/^whether\b/i.test(trimmed)` → YES ✓**

Returns `true`. The engine recognises the meaning as already question-shaped.

### `wrapInterrogativeForTemplate(meaning)` trace:

Input: lowercased meaning string  
- Line 198 (wh-questions): No match — starts with "whether"
- **Line 202: `isInterrogativeMeaning` → true**
- Returns: `stripTrailingPunctuation(meaning).trim()` = full proposition + rationale, no trailing punctuation

### Decision evidence path trace (line 1271-1273):

```js
if (isInterrogativeMeaning(meaning)) {  // YES ✓
    return `${wrapInterrogativeForTemplate(meaning)}?`;
}
```

Result: `"whether one prospective enterprise customer will sign if we launch this year; they account for ~£700k of the £1.2M expected annual revenue, so that resolving their intent is needed to assess the financial impact of launching now?"`

### Checkpoint 2 Answers:

| Question | Answer |
|---|---|
| Does engine recognise "whether..." as unresolved proposition? | **YES** — `isInterrogativeMeaning` returns true at line 189 |
| Does it convert "whether X..." into "Will/Does/Is X...?" | **NO** — no conversion logic exists; "whether" is treated as already interrogative |
| Does it merely append "?" | **YES** — direct from the full extracted string including rationale |
| Evidence framing applied? | **CONDITIONAL** — `buildEvidenceFallbackQuestion` would add "What evidence would confirm or rule out...", but in the decision reasoning path (line 1272-1273), interrogative means bypass the evidence template and go straight to append "?" |

## Checkpoint 3 — Why 60B.20 Looked Better

### 60B.20 source shape:
```
label: "Will our largest client leave if we relocate?"
description: "Uncertainty regarding whether our largest client would depart following a relocation to Manchester; matters because their departure would cost approximately £5M per year..."
```

**Label is already interrogative:** "Will our largest client leave if we relocate?"

### 60B.24 source shape:
```
label: "Prospective enterprise customer signing status"
description: "Whether one prospective enterprise customer will sign if we launch this year; they account for ~£700k of the £1.2M expected annual revenue, so that resolving their intent is needed to assess the financial impact of launching now."
```

**Label is nominal (noun phrase); proposition in description starting with "Whether"**

### First meaningful divergence: `extractMeaning` line 108

In 60B.24, the condition at lines 102-107 fires because the label contains "status" AND the description starts with "Whether". This causes `extractMeaning` to return the **full** `strippedDescription` (proposition + rationale after semicolon).

In 60B.20, the label is already interrogive ("Will our largest client..."). The condition at lines 102-107 does NOT fire because:
- Label contains no status/probability words (no "status" in "Will our largest client leave if we relocate?")
- Even though it has no "status", the label itself IS interrogative

The extracted meaning for 60B.20 is the **label** ("Will our largest client leave if we relocate?"), not the description. This is already a clean question, so the template simply appends "?" to produce a valid output.

### Quality difference cause: `description extraction` + `rationale contamination`

The root divergence is in `extractMeaning`:
1. **60B.20** — Label is interrogative → meaning = label (clean) → output = label + "?" ✓
2. **60B.24** — Label triggers status condition → meaning = full description including rationale after semicolon → output = proposition+rationale + "?" ✗

The quality difference comes from **description extraction capturing rationale** and the **absence of "whether→direct-question conversion"**.

## Cause Classification: C (Both A + B)

### A — RATIONALE EXTRACTION TOO BROAD
`extractMeaning` line 108 returns `sentenceCase(strippedDescription)` which includes everything after the semicolon. There is no internal delimiter logic for separating proposition from explanatory rationale.

### B — NO WHETHER→QUESTION CONVERSION
The engine recognises "whether X" as already interrogative (line 189) and passes it through unchanged. No conversion to "Will/Does/Is X?" exists in the codebase. The `isInterrogativeMeaning` function treats "whether" clauses as complete interrogatives rather than treating them as unresolved propositions that need conversion.

## Current Semantic Contract

**For a selected unknown whose explicit meaning is "whether X", what should deterministic formulation ideally represent?**

### C — Direct Interrogative: "Will/Does/Is X?"

The current code's intent (lines 170-189, 202-203) is:
- If the extracted meaning is already interrogative (wh- question, aux inversion, or whether-clause), pass it through unchanged.
- The rationale for line 189 treating "whether" as complete interrogative was to prevent double-wrapping ("What would clarify are...").

However, this conflates two distinct semantic states:
1. **Direct interrogative** (e.g., "Will X happen?") — ready as a question
2. **Indirect interrogative / unresolved proposition** (e.g., "whether X will happen") — needs conversion

The current contract treats both identically, which is why 60B.24's output preserves the indirect form with rationale contamination.

## Candidate Evaluations

### Candidate A — Strip Rationale Only

Extract only: `"Whether one prospective enterprise customer will sign if we launch this year"` (before semicolon). Then preserve existing formulation behaviour.

| Assessment | Value |
|---|---|
| Improves concision | **HIGH** — removes the entire explanatory clause |
| Produces conversational question | **NO** — "Whether one prospective enterprise customer will sign if we launch this year?" is still an indirect question (embedded/yes-no proposition form), not natural conversational English. The user would expect "Will one...?" |
| Risk of losing context | **LOW** — rationale is explanatory, not material. Materiality lives in the graph structure (£700k on edge/unknown node) |

### Candidate B — Deterministic Whether→Interrogative Conversion

Convert simple explicit propositions:
- Input: `"whether the customer will sign"`
- Output: `"Will the customer sign?"`

| Assessment | Value |
|---|---|
| Semantic robustness | **MEDIUM** — works for straightforward propositions but fails on complex conditionals ("whether we should launch if X AND Y") |
| Grammar complexity | **HIGH** — requires subject-auxiliary inversion, pronoun mapping, tense preservation, conditional clause handling |
| Meaning-change risk | **LOW** — "whether X" is semantically equivalent to "Will/Does/Is X?" in decision context |

### Candidate C — Clean Proposition + Evidence Framing

Strip rationale → formulate: `"What evidence would clarify whether the customer will sign if we launch this year?"`

| Assessment | Value |
|---|---|
| Semantic robustness | **HIGH** — "whether" is preserved as-is (no conversion needed); framing adapts to any proposition form |
| Conversational quality | **MEDIUM** — more formal than direct questions but still natural and decision-relevant. Standard in decision analysis literature |
| Consistency with existing `decision_evidence` family | **HIGH** — aligns with the evidence-gathering intent of the family (see line 1275 template) |

### Candidate D — Minimum Combination

**A + C**: Strip rationale first (Candidate A's extraction fix), then let existing evidence framing apply (producing Candidate C output). This avoids Candidate B's grammar complexity entirely.

## Decision Criteria Assessment

| Criterion | A | B | C | D (A+C) |
|---|---|---|---|---|
| 1. Remove explanatory rationale from question | PARTIAL | NO | YES | **YES** ✓ |
| 2. Preserve unresolved proposition | YES | YES | YES | **YES** ✓ |
| 3. Remains deterministic | YES | PARTIAL | YES | **YES** ✓ |
| 4. No provider rewriting | YES | YES | YES | **YES** ✓ |
| 5. No target selection change | YES | YES | YES | **YES** ✓ |
| 6. Preserve direct interrogative cases like 60B.20 | NO (breaks label path) | PARTIAL | YES | **YES** ✓ |
| 7. Avoid domain-specific grammar rules | YES | NO | YES | **YES** ✓ |

## Final Choice: D — MINIMUM COMBINATION

### Smallest implementation boundary

**One change to `extractMeaning`:**  
On line 108, instead of returning the full `strippedDescription`, split on semicolons and return only the first segment (the proposition), before applying `sentenceCase`.

```
Before: return sentenceCase(strippedDescription);
After:  return sentenceCase(strippedDescription.split(/;|[,]\s*(so\s+that|which\s+means)/i)[0].trim());
```

**No other changes required.** The existing decision-evidence formulation path (line 1272-1273) will then receive a clean proposition, and the `isInterrogativeMeaning` detection on line 189 will still correctly handle "whether" clauses as interrogative.

**Alternative boundary:** If you want cleaner output than "Whether X?" for all cases, also modify the decision path (line 1272-1273) to use `buildEvidenceFallbackQuestion` instead of direct append-for-interrogative-meaning when the meaning starts with "whether". This produces "What evidence would clarify whether X?" which is both natural and consistent with the evidence family.

## Implementation Readiness: A — READY FOR BOUNDED IMPLEMENTATION

One line change to `extractMeaning` at line 108 plus (optionally) one additional refinement in the decision path formatting logic.