Critical Thinking Framework
Overview
Critical thinking systematically evaluates arguments by decomposing them into claims, evidence, reasoning, and assumptions. It identifies where arguments are strong, weak, or fallacious — not to "win" debates but to arrive at better-justified conclusions.
Framework
IRON LAW: Separate the Argument from the Person
Evaluate the ARGUMENT (claim + evidence + reasoning), not the person
making it. A bad person can make a good argument. A trusted expert
can make a bad argument. Ad hominem (attacking the person) and appeal
to authority (trusting the person) are both fallacies.Argument Structure
Every argument has four components:
- Claim: What is being asserted? (conclusion)
- Evidence: What facts/data support the claim?
- Reasoning: How does the evidence support the claim? (the logical bridge)
- Assumptions: What unstated premises must be true for the reasoning to hold?
Evaluation Steps
Step 1: Identify the claim — What exactly is being argued? Restate in one sentence.
Step 2: Examine the evidence
- Is it factual or anecdotal?
- Is it sufficient (enough data points)?
- Is it relevant (does it actually relate to the claim)?
- Is it current (not outdated)?
- Could the evidence support a different claim?
Step 3: Evaluate the reasoning
- Does the evidence logically lead to the claim?
- Are there logical fallacies? (see catalog below)
- Is correlation being mistaken for causation?
- Are there alternative explanations?
Step 4: Surface assumptions
- What must be true for this argument to work?
- Are these assumptions reasonable?
- What happens if an assumption is wrong?
Common Logical Fallacies
| Fallacy | What It Does | Example |
|---|---|---|
| Ad hominem | Attacks the person, not the argument | "You can't talk about economics, you're not an economist" |
| Straw man | Distorts the opponent's argument to attack a weaker version | "You want to reduce military spending? So you want us defenseless?" |
| False dichotomy | Presents only two options when more exist | "You're either with us or against us" |
| Slippery slope | Claims one event will inevitably lead to extreme consequences | "If we allow remote work, soon no one will come to the office ever" |
| Appeal to authority | Uses authority status instead of evidence | "The CEO says AI will replace all jobs, so it must be true" |
| Hasty generalization | Draws broad conclusion from limited cases | "My two friends who studied art are unemployed, so art degrees are useless" |
| Red herring | Introduces irrelevant information to distract | "Yes, our product has bugs, but look at our amazing company culture" |
| Circular reasoning | Conclusion is assumed in the premise | "This is the best approach because there's no better one" |
Output Format
# Argument Analysis: {Topic}
## Claim
{One-sentence restatement of the core argument}
## Evidence Assessment
| Evidence | Type | Sufficient? | Relevant? | Current? |
|----------|------|------------|-----------|----------|
| {evidence 1} | {fact/anecdote/expert/stat} | Y/N | Y/N | Y/N |
## Reasoning Evaluation
- Logical validity: {valid / fallacious}
- Fallacies detected: {list with explanation}
- Alternative explanations: {what else could explain the evidence}
## Hidden Assumptions
1. {assumption} — reasonable? {Y/N, why}
## Verdict
- Argument strength: Strong / Moderate / Weak
- Key weakness: {the biggest flaw}
- What would strengthen it: {what evidence or reasoning is missing}Examples
Correct Application
Scenario: Evaluating the claim "Remote work reduces productivity"
- Claim: Remote work reduces productivity
- Evidence cited: "Our Q3 output dropped 15% after going remote"
- Assumption surfaced: That the output drop was CAUSED by remote work (not by Q3 seasonality, new hires ramping up, product pivot, or pandemic stress)
- Fallacy: Post hoc ergo propter hoc (after it, therefore because of it) — correlation assumed to be causation
- Verdict: Weak — single data point, confounded by multiple factors, no controlled comparison ✓
Incorrect Application
- "The CEO said remote work is bad, so the argument must be wrong" → Ad hominem in reverse (dismissing based on who said it). Violates Iron Law: evaluate the argument, not the person.
Gotchas
- Strong arguments can have wrong conclusions: An argument can be logically valid (reasoning follows from premises) but unsound (premises are false). Check both.
- "I feel" is not evidence: Emotions are valid as human experiences but not as evidence for factual claims. "I feel unsafe" is a legitimate concern; "I feel this policy doesn't work" is not evidence of policy failure.
- Burden of proof: The person making the claim bears the burden of proof. "You can't prove it's wrong" is not evidence that it's right (argument from ignorance).
- Steelmanning > strawmanning: Instead of attacking the weakest version of an argument (strawman), construct the STRONGEST version (steelman) and then evaluate it. This produces better analysis.
- Critical thinking is not cynicism: The goal is better-justified beliefs, not skepticism of everything. Some arguments are strong. Acknowledging strong arguments is part of critical thinking.
References
- For formal logic notation and syllogisms, see
references/formal-logic.md - For fallacy catalog with extended examples, see
references/fallacy-catalog.md