logic_and_fallacies v1.0.0

name: "logic_and_fallacies" description: "Stress-tests reasoning before it goes out: names common argument flaws (straw man, ad hominem, false dilemma, etc.), runs a check-yourself-first self-audit, and steelmans the other side before rebutting. Triggers on debates, argument evaluation, persuasive writing, reviewing claims, or any 'is this reasoning sound?' question." metadata: { "includeInPrompt": true }

Logic & Fallacies

Purpose

Bad reasoning is the most common failure mode in agentic work — and the fallacy label is the most abused correction in discourse. This skill does three jobs in order: (1) audit your own reasoning before asserting anything, (2) steelman the opposing position before attacking it, (3) name flaws in arguments precisely — with the exact break point, never as a drive-by label. The fallacy catalog lives in references/fallacy-field-guide.md; a full worked run-through is in references/worked-example.md.

Workflow

1. Extract the argument

Write out the argument in this shape before judging it:

• Claim: what is being asserted?
• Premises: what reasons or evidence are offered?
• Inference: how do the premises connect to the claim?

If there is no argument — just a bare claim, an insult, or a preference — say so and stop. Not everything is a fallacy; sometimes it's just an unsupported opinion.

2. Check yourself first

Before flagging anything in someone else's reasoning, audit your own. Run the self-check:

1. What am I treating as true that I haven't verified?
2. What evidence do I actually have, versus what feels true?
3. Would I still believe this if the conclusion were inconvenient to me?
4. What's the strongest objection a smart skeptic would raise — and can I answer it?

This is where motivated reasoning lives: reasoning toward the conclusion you want. If you can't pass your own audit, don't proceed to judge anyone else's.

3. Steelman before you strike

Construct the strongest possible version of the position you're evaluating or opposing — the "steel man," the deliberate opposite of the straw man. Ask:

• What premises must be true for this to hold?
• What is the best evidence a fair opponent would bring?
• Under what boundary conditions would this actually be right?

If the steel-manned version holds, say so plainly. Updating your view is not losing an argument — it is the entire point of having one. Charity is not surrender: you steelman to test ideas against their strongest form, not to agree with them.

4. Scan for flaws — carefully

Use references/fallacy-field-guide.md for the recognition patterns. But do not pattern-match mechanically. Before naming a fallacy, check whether context, domain knowledge, or a non-obvious valid inference justifies what looks fallacious — e.g., citing a doctor on medicine is evidence, not appeal to authority; a genuine dilemma is not a false one. The label is only earned when you can point to the exact sentence where the reasoning breaks.

5. Deliver the verdict

State one of:

• Sound: conclusion follows from true premises; show the inference chain.
• Flawed: name the fallacy, quote the break point, and provide a repaired version of the argument (strongest valid form of what they were trying to say).
• Undecidable on current evidence: say what's missing and how to test it.

Output Contract

Every analysis reports:

1. The extracted argument (claim / premises / inference).
2. The self-check result (what you verified, what you didn't).
3. The steel man (strongest version of the other side).
4. The verdict: sound, flawed (named fallacy + break point + repair), or undecidable.

Operating Rules

1. Accuracy first. Every factual claim in a skill must be verified via web search or a primary source. Never invent numbers, dates, quotes, or events. Unverifiable = cut it or frame as opinion. No confident unverified claims, ever.
2. Never drop a fallacy name without quoting the exact words where the reasoning breaks. A label without a break point is itself a dodge.
3. Steelman first, always. If you skipped step 3, you didn't earn step 4.
4. Citing relevant expertise is evidence, not "appeal to authority." Popularity, tradition, and emotion are not evidence — unless the question is about popularity, tradition, or emotion.
5. Correlation is never causation until a mechanism is shown. One example is never "everyone" or "always."
6. Don't use fallacy-spotting to win. Using "that's a straw man" as a shutdown is performance, not truth-seeking — and the skill is wasted there.
7. Keep SKILL.md tight; the catalog and worked examples stay in references/.