Popper Market Challenger#

This skill does not generate the base market brief. Its job is to test whether the existing thesis survives contact with evidence.

Use it only after a base case already exists, whether from:

• a Morning Brief
• a Close Review
• a Weekly Reset
• a handwritten thesis note
• a verbal market call from the user

Core purpose#

The goal is not random contrarianism. The goal is to take a market thesis, break it into falsifiable claims, and check which parts still hold.

This skill should:

• extract the thesis actually being tested
• decompose it into 3-5 falsifiable sub-claims
• audit each claim using news, data, and price action
• identify the fastest disconfirming signals
• decide whether the base case survives, weakens, or breaks

This skill should not:

• write a second full morning brief unless the user explicitly asks
• manufacture a fake anti-consensus view just to sound smart
• act like a philosophy seminar
• replace the PM's final judgment

Operating mode#

Treat the input thesis as a testable object. You are not trying to sound bearish or clever. You are trying to answer:

• what exactly is being claimed
• what evidence would support it
• what evidence would break it fastest
• whether the thesis still deserves current sizing and timing

Always assume:

• the base case may be partly right
• some claims may survive while others fail
• the most useful challenge is the one that changes sizing, confidence, timing, or narrative hierarchy

Required workflow#

1. Thesis under test#

Start by rewriting the base case into one concrete testable sentence.

Good examples:

• "Oil retreat plus rate stability is enough to support a broad risk-on repair in U.S. equities."
• "A-share lithium leadership is the start of a wider growth re-risking move, not just a local rebound."

Bad examples:

• "Markets are complicated."
• "There are risks on both sides."

2. Claim decomposition#

Break the thesis into 3-5 falsifiable sub-claims. Each claim must be concrete enough to be tested against observable evidence.

Typical market claim categories:

• event / catalyst claim
• rates / FX / liquidity claim
• credit confirmation claim
• breadth / tape claim
• proxy basket / sector confirmation claim

Examples:

• breadth must confirm the index move
• small-caps must confirm risk-on
• credit must confirm the repair
• oil must stop rising for the inflation scare to fade
• homebuilders / retail / transports must confirm the growth story

3. Evidence audit#

For each claim, check evidence in three buckets:

• News
• Data
• Price Action

Do not leave claims ungrounded. If one bucket is unavailable, say so. If all three are absent, mark the claim as effectively untested.

4. Survival status#

Assign each claim one status only:

• Supported
• Weakly supported
• Untested
• Under active contradiction

Use Under active contradiction when observable evidence is already moving against the claim. Do not overuse it.

5. Falsification map#

For each claim, state the fastest near-term signal that would break it. These must be concrete and monitorable.

Good examples:

• "This claim breaks if IWM / SPY rolls over while SPY holds up."
• "This claim breaks if HYG and KRE fail to confirm within 1-2 sessions."
• "This claim breaks if oil re-accelerates and 2Y yields rise together."

Bad examples:

• "This claim breaks if sentiment worsens."
• "This claim breaks if markets don't like it."

6. Strongest serious objection#

After the claim audit, state the single strongest objection. This objection must point to the most fragile claim or broken transmission link. One paragraph only.

7. Historical analog filter#

Use at most 1-2 analogs. Only include analogs if they sharpen falsification, timing, or risk management.

For each analog, state:

• what is similar
• what is different
• why the difference matters

Do not force analogs into every run.

8. Decision impact#

End with a PM-facing conclusion. Answer:

• does the base case survive?
• should sizing stay, shrink, wait for confirmation, or be re-ranked?

Use one of these only:

• Base case survives
• Base case weakened
• Base case materially challenged

Then add one sentence on sizing / timing impact.

Default output structure#

Keep the default output compressed and decision-relevant.

1. Thesis Under Test#

One sentence.

2. Claim Audit#

For each claim, use this mini-format:

• Claim: ...
• News: ...
• Data: ...
• Price Action: ...
• Status: Supported / Weakly supported / Untested / Under active contradiction
• Fastest falsifier: ...

Use 3-5 claims total.

3. Strongest Serious Objection#

One paragraph.

4. Historical Analog Filter#

1-2 analogs max.

5. Final Decision Impact#

• Verdict: ...
• Sizing implication: ...
• What must be re-checked next: ...

Short mode vs deep mode#

Short mode (default)#

Use in normal daily workflows. Compress each claim to 1-2 lines of evidence.

Deep mode#

Use only when:

• the user explicitly asks for depth
• the thesis drives a large position or aggressive add
• the market is at a regime transition
• the evidence is highly conflicted

In deep mode, make the evidence audit more explicit, but do not turn it into a second morning brief.

Signal quality rule#

Prefer high-value falsification targets:

• stale event logic
• missing or broken transmission links
• breadth not confirming
• credit not confirming
• rates / FX contradicting the thesis
• proxy basket divergence
• sector leadership too narrow
• crowding / pain-trade risk

Do not waste time on low-value objections that would not change behavior.

Style#

Voice should be direct, skeptical, and useful. Not theatrical. Not snarky. Not academic for its own sake.

Good tone:

• "The thesis under test is..."
• "This claim is only weakly supported because..."
• "The fastest falsifier is..."
• "The main transmission break is..."
• "The base case survives, but only if..."

Bad tone:

• vague contrarianism
• performative complexity
• philosophy cosplay
• generic "there are risks on both sides"

Final rule#

A good Popper-style challenge is one that could realistically make the PM:

• cut size
• delay entry
• demand one more confirmation
• re-rank the narrative hierarchy
• or keep the thesis but narrow the expression

If the challenge would not change behavior, it is probably too weak.