Top 100 Vocabulary for Adults | Critical Thinking

Critical thinking is not the habit of disagreeing with everything. It is the discipline of asking what is being claimed, what supports it, what would count against it, which assumptions are carrying the argument, and how strongly the conclusion deserves to be held.

This flagship belongs to the eduKate Adult Vocabulary for Professionals system. It extends the evidence and reasoning language introduced in Advanced Professional English into an explicit critical-thinking toolkit for professional adults.

The Four Banks

Claims & Evidence: claim, assertion, proposition, premise, conclusion, evidence, source, fact, observation, inference, interpretation, assumption, hypothesis, rationale, support, corroborate, substantiate, verify, validate, refute, qualify, caveat, uncertainty, confidence, burden.

Logic & Structure: argument, valid, sound, coherent, consistent, contradiction, implication, entailment, relevance, sufficient, necessary, condition, criterion, distinction, category, analogy, comparison, causal, correlation, mechanism, counterexample, exception, generalisation, extrapolation, counterfactual.

Bias & Error: bias, prejudice, heuristic, anchoring, confirmation bias, availability bias, framing, selection bias, survivorship bias, hindsight bias, overconfidence, motivated reasoning, cherry-picking, false dilemma, straw man, ad hominem, circular reasoning, equivocation, ambiguity, fallacy, distortion, omission, confounding, base rate, anecdotal.

Judgement & Revision: plausible, credible, probable, possible, tentative, provisional, robust, representative, material, significant, proportionate, nuanced, sceptical, open-minded, revise, reconsider, update, challenge, test, discriminate, compare, weigh, prioritise, conclude, suspend judgement.

Top 100 Critical-Thinking Words: Working Meanings

#	Word	Professional meaning
1	Claim	A statement presented as true and open to support or challenge.
2	Assertion	A confidently stated claim, not necessarily supported.
3	Proposition	A statement or idea put forward for consideration or testing.
4	Premise	A starting statement on which an argument depends.
5	Conclusion	A judgement reached from premises or evidence.
6	Evidence	Information that supports or challenges a claim.
7	Source	The origin of information or testimony.
8	Fact	A statement that can be established as true or false through reliable evidence.
9	Observation	Something directly noticed, measured or recorded.
10	Inference	A conclusion drawn from evidence rather than directly observed.
11	Interpretation	An account of what information means.
12	Assumption	A proposition accepted for reasoning without complete proof.
13	Hypothesis	A testable explanation or prediction.
14	Rationale	The reasoning that explains why a claim or action makes sense.
15	Support	Reasons or evidence favouring a claim.
16	Corroborate	Add independent evidence that supports an account.
17	Substantiate	Provide enough evidence to support a claim.
18	Verify	Check a claim against evidence or source.
19	Validate	Show that a method, measure or model is suitable for its intended use.
20	Refute	Show that a claim is false or unsupported.
21	Qualify	Limit or refine a claim by adding conditions.
22	Caveat	A warning or limitation affecting interpretation.
23	Uncertainty	Incomplete knowledge about a value, event or conclusion.
24	Confidence	The degree of certainty justified by available evidence.
25	Burden	The responsibility to provide support for a claim.
26	Argument	A connected set of reasons offered for a conclusion.
27	Valid	Structured so that, if premises are true, the conclusion follows.
28	Sound	Valid in structure and based on true or well-supported premises.
29	Coherent	Logically connected and mutually fitting.
30	Consistent	Free from relevant contradiction.
31	Contradiction	Two claims that cannot both be true in the same sense.
32	Implication	A consequence or meaning that follows from a claim.
33	Entailment	A relationship in which one statement necessarily follows from another.
34	Relevance	Direct connection to the question being judged.
35	Sufficient	Enough to meet the purpose or support required.
36	Necessary	Required for something else to hold or occur.
37	Condition	A requirement on which a claim, decision or outcome depends.
38	Criterion	A standard used to evaluate a claim or option.
39	Distinction	An important difference between similar concepts.
40	Category	A class used to group things sharing relevant properties.
41	Analogy	A comparison used to reason from similarity.
42	Comparison	Examination of similarities and differences.
43	Causal	Relating to cause and effect.
44	Correlation	An association between variables that does not by itself prove causation.
45	Mechanism	The process through which a cause produces an effect.
46	Counterexample	A case showing that a general claim does not always hold.
47	Exception	A case not covered by a general rule.
48	Generalisation	A wider claim drawn from particular cases.
49	Extrapolation	An estimate extending beyond observed evidence.
50	Counterfactual	A reasoned account of what might have happened under different conditions.
51	Bias	A systematic tendency that distorts judgement or evidence.
52	Prejudice	Pre-judgement not adequately based on evidence.
53	Heuristic	A mental shortcut useful for speed but vulnerable to error.
54	Anchoring	Over-reliance on an initial value or idea.
55	Confirmation bias	Preference for evidence supporting an existing belief.
56	Availability bias	Judging likelihood by how easily examples come to mind.
57	Framing	The way a problem is presented, influencing attention and judgement.
58	Selection bias	Distortion caused by a non-representative selection process.
59	Survivorship bias	Focusing on visible successes while ignoring failures that disappeared.
60	Hindsight bias	Seeing an outcome as more predictable after it happened.
61	Overconfidence	Greater certainty than evidence warrants.
62	Motivated reasoning	Reasoning shaped by a preferred conclusion.
63	Cherry-picking	Selecting evidence that favours one view while ignoring contrary evidence.
64	False dilemma	Presenting only two options when more exist.
65	Straw man	Misrepresenting an argument so it is easier to attack.
66	Ad hominem	Attacking a person instead of addressing the argument.
67	Circular reasoning	Using the conclusion as part of its own support.
68	Equivocation	Shifting the meaning of a word within an argument.
69	Ambiguity	More than one reasonable interpretation.
70	Fallacy	A recurring error in reasoning.
71	Distortion	A representation that changes important features of reality.
72	Omission	Leaving out information that may affect interpretation.
73	Confounding	A third factor distorting an apparent relationship.
74	Base rate	The underlying frequency of an event before case-specific evidence is considered.
75	Anecdotal	Based mainly on individual cases rather than systematic evidence.
76	Plausible	Reasonably possible given what is known.
77	Credible	Worthy of belief given source and evidence.
78	Probable	More likely than not or judged relatively likely.
79	Possible	Capable of occurring, without implying high likelihood.
80	Tentative	Cautious and not firmly established.
81	Provisional	Accepted for now but subject to revision.
82	Robust	Strong enough to survive reasonable challenge or variation.
83	Representative	Reflecting relevant characteristics of the wider population.
84	Material	Important enough to influence judgement.
85	Significant	Meaningful or important; sometimes technically defined.
86	Proportionate	Appropriate in scale relative to need or evidence.
87	Nuanced	Recognising important shades of difference.
88	Sceptical	Requiring adequate reasons before accepting a claim.
89	Open-minded	Willing to revise belief when evidence changes.
90	Revise	Change a judgement in response to new evidence.
91	Reconsider	Examine a judgement again.
92	Update	Adjust a belief or estimate as new information arrives.
93	Challenge	Test a claim through reasoned questioning.
94	Test	Subject a claim or method to evidence or conditions.
95	Discriminate	Distinguish between competing explanations or categories.
96	Compare	Evaluate similarities and differences.
97	Weigh	Judge competing evidence or considerations.
98	Prioritise	Give precedence according to relevance or importance.
99	Conclude	Reach a reasoned judgement.
100	Suspend judgement	Delay conclusion because evidence is insufficient.

Critical Thinking Begins by Separating Layers

A professional statement often contains several layers compressed into one sentence. “The supplier is unreliable and will probably miss the next deadline” may contain a fact, interpretation and forecast. Perhaps the fact is that three dates were missed. “Unreliable” is a judgement. “Will probably miss” is a prediction. Critical thinking makes the layers visible so each can be tested at the right strength.

Claim vs Evidence

A claim is what someone wants you to believe. Evidence is what they offer in support. Seniority, confidence and fluency can make a claim feel like evidence, but they are not substitutes for it. Ask: what observation, record, comparison or source would make this claim more or less credible?

Valid vs Sound

An argument can be valid in structure yet unsound because a premise is false. “All projects over budget fail. This project is over budget. Therefore it will fail.” The structure is valid if the first premise were true, but the premise itself is indefensible. Professionals often debate conclusions when they should be testing premises.

Necessary vs Sufficient

A necessary condition must be present; a sufficient condition is enough by itself. Funding may be necessary for a project to proceed but not sufficient for success. Approval may be necessary for launch but not sufficient if testing is incomplete. Confusing these produces exaggerated conclusions.

Correlation, Mechanism and Counterfactual

Correlation asks whether two variables move together. Mechanism asks how one could produce the other. Counterfactual asks what would likely have happened without the alleged cause. Together, these three questions are a powerful defence against simplistic causal stories.

The Strongest Counterexample Test

If someone says “remote work always reduces collaboration,” ask for a case where remote work produced strong collaboration. One valid counterexample is enough to defeat “always,” even if it does not prove the opposite. Extreme words—always, never, everyone, no one—carry unusually heavy burdens.

Bias Is Not a Character Flaw

Cognitive bias is part of normal reasoning. The professional question is not “Am I biased?” but “Which bias would be easiest for me to fall into here, and what procedure can reduce its effect?” Blind review, pre-defined criteria, base-rate data and independent challenge are examples of structural defences.

Anchoring in Real Work

The first budget figure, salary expectation, valuation, schedule estimate or diagnosis can anchor later judgement. A useful practice is to estimate independently before seeing the proposed number. Once the anchor is visible, “adjusting away from it” often does not fully remove its influence.

Confirmation Bias and Search Design

Do not ask only, “What evidence supports my view?” Also ask, “What evidence would I expect to see if my view were wrong?” A good investigation is designed to discriminate between explanations, not merely accumulate supporting examples.

False Dilemma in Professional Decisions

“Either we launch now or we lose the market” may omit staged launch, limited geography, temporary manual controls, feature reduction or revised commercial terms. When a discussion becomes binary too quickly, ask what third option exists.

Straw Man vs Steel Man

A straw man weakens another person’s position before attacking it. A stronger habit is to “steel man”: state the opposing argument in a form its strongest advocate would accept, then test it. This reduces theatre and increases decision quality.

Anecdote vs Base Rate

A vivid example can dominate judgement even when it is statistically unusual. Before concluding from a memorable case, ask the base rate: how often does this outcome occur in comparable cases? One dramatic failure can matter greatly, but it should not silently become evidence that every case is equally likely to fail.

Plausible Is Not Probable

A scenario can be plausible—consistent with what we know—without being the most likely explanation. Professionals often over-promote plausible stories because they are coherent. Coherence is helpful; probability still needs evidence.

Critical Thinking Is Revision-Friendly

The mature thinker treats belief as updateable. Changing your mind after stronger evidence is not intellectual weakness; refusing to update can be. The language of tentative, provisional, qualified and robust conclusions makes revision normal rather than embarrassing.

Professional Scenario: The Successful Pilot

A pilot improves output by 20%. Participants volunteered, managers gave the pilot extra attention, and demand was unusually low. Build the reasoning chain: observation → possible confounders → alternative hypotheses → what evidence would discriminate → provisional conclusion. Do not jump directly from “20% improvement” to “roll out everywhere.”

Professional Scenario: The Star Employee

A manager says, “Every successful project I’ve seen had a charismatic leader, so charisma is essential.” Identify survivorship bias, possible selection bias, missing counterexamples and the difference between necessary and sufficient conditions.

Professional Scenario: The Urgent Investment

A colleague says, “Everyone is investing now. If we wait, we will fall behind.” Ask: what is the base rate of successful investments? What does “everyone” mean? What evidence shows timing rather than execution quality is the decisive factor? What alternative preserves optionality?

Seven-Day Critical-Thinking Ownership Plan

Day	Focus	Practice
1	Claims	Label ten statements as fact, inference, assumption or recommendation.
2	Logic	Identify premises and conclusions in five arguments.
3	Causation	For one correlation, list three alternative mechanisms.
4	Bias	Find two biases that could affect a current decision.
5	Counterargument	Steel-man the strongest opposing view.
6	Retrieval	Recall 75+ words by reasoning job.
7	Transfer	Write a one-page critical review of a real proposal.

Critical-Thinking Diagnostic

• Can you separate observation from inference?
• Can you identify the premise carrying a conclusion?
• Can you distinguish necessary from sufficient conditions?
• Can you name a plausible confounder?
• Can you give a counterexample to an over-general claim?
• Can you identify a base rate before using an anecdote?
• Can you state what evidence would change your mind?
• Can you suspend judgement when evidence is insufficient?

Continue the Thinking Wing

• Analytical Reasoning
• Problem Solving
• Decision-Making & Judgement
• Adult Vocabulary for Professionals Hub

Conclusion

Critical thinking is not permanent doubt. It is calibrated belief. It helps a professional know when evidence is strong enough to act, when a claim needs qualification, when a familiar story is hiding an assumption, and when the most intelligent answer is still: we do not yet know.