Critical thinking

Learning guide and study notes

Make your reasoning visible. Check claims against evidence and alternatives, then revise your confidence when the evidence changes.

What you will learn

Separate an observation from an interpretation or claim.
Test a claim against rival explanations and disconfirming evidence.

What is it?

Critical thinking is purposeful, self-correcting judgment: separating raw evidence from claims and assumptions, testing competing explanations, and calibrating your confidence to the strength of the proof.

The Delphi expert consensus describes critical thinking as purposeful, self-regulatory judgment: interpreting, analyzing, evaluating, inferring, explaining, and correcting one’s reasoning. It also emphasizes curiosity, fairness, and willingness to reconsider—not habitual disagreement [1].

Core question: What should we believe or decide—and why is that judgment warranted?
When to use it: When evaluating vendor pitches, incident post-mortems, bold proposals, or disputed claims.

Tools and techniques

Key techniques

Claim–evidence–assumption splitSeparate observations, interpretations, forecasts, and recommendations from unstated premises.
Analysis of Competing HypothesesTest the same evidence against rival explanations and actively look for disconfirming facts.
Conditional confidence statementState current confidence alongside the concrete observation that would revise the judgment.

Procedure: think it through step by step

Frame the question
What exactly must be believed or decided? Define ambiguous terms and the stakes.
Separate claim and evidence
Is this an observation, interpretation, forecast, value judgment, or recommendation? Who produced the evidence, and what is missing? [1]
Test the bridge
Which assumptions connect the evidence to the claim? What other explanation fits? Seek a fact that could weaken your preferred answer [2].
Conclude with a condition
State your current confidence and its limits: “Given __, I lean __; I would change my view if __.” Plan, monitor, and evaluate the reasoning, not just the final answer [3].

Visual guide

Workflow chart: Critical thinking — **Workflow**From situation through deliberate steps to output

Mind map: Critical thinking — **Mind map**Four connected questions to keep in view

Worked example · “This tool saves everyone time”

Claim: “An AI meeting-summary tool will save everyone time, so we should roll it out company-wide.”

Evidence: A demo took five minutes to summarize one meeting. That observation is relevant but cannot establish the net effect across roles and meetings.

Hidden assumptions: Editing and checking take little time; the summaries are accurate enough for their purpose; privacy obligations permit the workflow; the measured meeting is representative.

Rival explanations: A short or unusually structured meeting may be easy to summarize; reviewers might spend more time correcting errors than they save.

Better judgment: “The demo is promising, but not evidence for a company-wide rollout. Pilot a permitted use case; measure total preparation, review, and correction time alongside error rates. Expand only if the agreed thresholds are met.”

This is a fictional teaching example, not a measured product study. The reasoning follows the Delphi emphasis on evaluation and self-correction [1] and the structured examination of assumptions and alternatives [2].

A 15-minute claim clinic

Use a claim you already believe.

Write its exact wording, one supporting observation, the assumption connecting them, one plausible rival explanation, and a piece of evidence that would change your mind. End with a two-sentence conclusion that distinguishes what you know from what you infer.

For online sources, read laterally: Leave an unfamiliar site to investigate who is behind it and what independent sources say. A classroom study found improved digital-credibility judgments after instruction in this approach; that result does not make every web claim easy to verify [4].
For unfamiliar domains, learn the subject: A checklist cannot replace relevant knowledge. Practice reasoning with concrete content and reflect on your process—plan, monitor, evaluate [3].
For disagreement, ask a fair question: What would the other person identify as the strongest evidence against your view? Then test that evidence rather than debating personalities [1].

Critical thinking aims at a better-supported judgment, not automatic skepticism or certainty.

Review and make it your own

The idea to remember

A credible judgment shows the evidence, the assumptions connecting it to the claim, and what would change your mind.

An outline for your notes

Use a problem of your own. Write a short answer to each prompt, then return after trying the method.

Claim: write the exact statement being evaluated.
Support: separate evidence from the assumption that connects it to the claim.
Revision: name a rival explanation and a fact that would change your confidence.

Check your understanding

Answer from memory before opening the suggested answer.

Does a confident speaker provide stronger evidence?

Compare with a suggested answer

No. Confidence is a presentation cue. Evaluate the source, relevance, method, and whether independent evidence supports the claim.

What is missing from “the change caused the outage because it happened first”?