Counterfactual Prober — Active Disconfirmation
Spelunker's existing Phase 5 adversarial search asks: "has anyone written 'X is wrong'?" That's passive — it only finds critique that already exists. This skill asks the harder question: "if X were wrong, what should we observe in the world that we haven't yet looked for?" — and then goes and looks for those signatures.
This is the difference between reading reviews of a movie and watching the movie yourself.
Guiding Principles
- Predictions, not opinions. A counterfactual is a falsifiable observation, not a belief. "If passive flows are NOT 68% of the market, we should see active funds outperforming index funds over the same period."
- Look for the signature, not the conclusion. Search for the empirical pattern, not for someone else who already concluded the original claim is wrong.
- Absence of the signature is weak evidence FOR the claim. Presence of the signature is strong evidence AGAINST.
- Probe the load-bearing claims, not the trivia. Counterfactual probing is expensive — apply it to claims whose downgrade would change the brief's overall conclusion.
How to Run
Input
- The synthesized brief from
evidence-synthesizer(after the existing Phase 5 adversarial search has run) - The dependency graph from
claim-decomposer - Depth mode:
standard(probe top 1 critical claim) ordeep(probe all critical claims and the highest-priority supporting claims)
Steps
Step 1 — Select Claims to Probe
Identify load-bearing claims:
- All claims tagged Confirmed or Likely that are flagged
criticalpriority - Plus, in
deepmode, the top 2 Likely-taggedsupportingclaims (downgrading these would cascade through the dependency graph)
Skip:
- Speculative or Contested claims (already low-confidence; counterfactual would not change much)
- Definitional claims (no empirical signature to probe)
- Claims already invalidated in the existing Phase 5 adversarial search
Step 2 — Generate Counterfactual Predictions
For each selected claim, generate 2-4 specific empirical predictions of the form:
"If [claim] were FALSE, then we should observe [specific empirical pattern] because [causal mechanism]."
Examples:
Claim: "Passive flows are ~68% of the US fund market as of mid-2025."
- CF1: We should see significant active-fund outperformance vs. index over 2020-2025 (active managers would beat the benchmark if they were actually running most of the money).
- CF2: Index reconstitution events should NOT cause measurable price dislocations (no concentrated passive bid).
- CF3: Mega-cap concentration should be stable or declining (passive flows are what's accumulating in mega-caps).
Claim: "Drug X reduces mortality by 30% in population Y."
- CF1: Healthcare mortality stats for population Y should NOT show a divergence after Drug X's approval.
- CF2: Insurance actuarial tables for Y should show similar mortality before/after market access.
- CF3: Replications of the trial in other populations should fail to find the effect.
The predictions must be:
- Specific — name a measurable quantity, time window, and direction
- Independent of the original evidence — don't search the same studies that grounded the original claim
- Mechanistically motivated — explain WHY the signature should appear if the claim is false
Step 3 — Search for Each Signature
For each counterfactual prediction, run a focused search using source-triangulator (or directly via WebSearch if simpler). Look for the empirical pattern, not for the conclusion.
Bad search: "passive ownership share is not 68%" (looking for the conclusion)
Good search: "active vs passive fund performance 2020-2025 cumulative return" (looking for the signature)
Record per prediction:
- The search queries used
- What was found (the actual empirical observation, not someone's interpretation)
- Whether the signature is
present(CF supported, original claim weakened),absent(CF refuted, original claim strengthened), ormixed/inconclusive
Step 4 — Update Confidence Tags
For each probed claim, aggregate the counterfactual results:
| Result pattern | Effect on claim |
|---|---|
| All CFs absent (signatures of falsity NOT found) | Confirmed stays Confirmed; Likely upgraded to Confirmed if other criteria met |
| Most CFs absent, 1 mixed | No change (confidence stays where the original adversarial search left it) |
| ≥1 CF present (signature of falsity FOUND) | Downgrade by one tier and feed into evidence-synthesizer for cascade re-run |
| Most CFs inconclusive (couldn't measure the signature) | No change, but document the limit in Gaps |
The downgrade then triggers the existing Phase 5 backpropagation cascade through the dependency graph.
Output
Append to the brief a new section between Phase 5's existing output and Phase 6's presentation:
COUNTERFACTUAL PROBE
────────────────────
Claims probed: <N>
For each claim:
Claim <id>: "<text>"
Original confidence: <tier>
CF1: If false, we'd observe: <prediction>
Searched: <queries>
Found: <observation>
Verdict: signature [present | absent | inconclusive]
CF2: ...
Aggregate: <signature pattern> → confidence change: <tier> → <tier> | unchanged
Cascade triggered: yes | no
If yes: list of dependent claims also re-evaluated
Error Handling
No CFs are searchable (claim is too abstract or about future events): Document as a known limit; do not invent searches that don't bear on the claim. Return "no probe possible" for that claim.
All CFs return inconclusive (data simply isn't there): This is itself worth noting — it means the claim is essentially unfalsifiable with current data, which should soften any high-confidence tag. Recommend downgrading Confirmed to Likely on grounds of "unfalsifiable in practice."
Search results contradict the original claim AND the counterfactual signature is present: Strong evidence of error in the original brief. Surface this prominently and recommend a Phase 4 re-run, not just a tag downgrade.
Scope Boundaries
Does NOT: Replace the passive adversarial search in Phase 5 — it complements it. Does NOT: Probe every claim. Token cost is too high. Apply to load-bearing claims only. Does NOT: Generate predictions for claims that are inherently non-empirical (definitions, value judgments, predictions about pure preference).