Evidence, Source Evaluation and Logical Fallacies: every key term you need (+ practice quiz)
25 flashcard terms for College Writing & Rhetoric Topic 4, written to match the course framework. Study them here, then drill them as interactive flashcards, or test yourself with the 15-question quiz — free, no account needed.
Whether enough support has been given for the size of the claim being made. A sweeping generalisation resting on two anecdotes fails here even if both anecdotes are accurate.
Relevance of evidence
Whether the material actually bears on the point at issue rather than on a neighbouring one. Irrelevant but impressive evidence is one of the commonest ways papers create false confidence.
Representativeness
Whether the cases cited reflect the wider population being described. A sample drawn only from volunteers may be accurate about volunteers and misleading about everyone else.
Primary source
A record produced within the event or by the original investigator, such as a letter, a data set, or an interview transcript. It offers direct access at the cost of requiring interpretation.
Secondary source
A work that interprets, synthesises, or comments on primary material, such as a review article or a scholarly monograph. It gives context but carries the author's framing with it.
Tertiary source
A compilation that digests other sources, such as an encyclopedia or a textbook summary. It is useful for orientation and rarely appropriate as the main support for a contested claim.
Peer review
The process in which anonymous specialists assess a manuscript before publication. It filters obvious error and inflated claims but does not certify a finding as true or final.
Currency of a source
How recent the material is relative to the pace of change in its field. Currency matters intensely in fast-moving research areas and much less for historical or theoretical work.
Authority of a source
The basis of the author's or publisher's standing, including training, institutional position, and record of accountable work. Authority is domain-specific and does not transfer across fields.
Source bias
A systematic tilt arising from the producer's interests, funding, or commitments. Bias does not automatically disqualify a source, but it does dictate how the source is used and framed.
Lateral reading
Evaluating an unfamiliar source by leaving it and checking what independent parties say about the publisher and author, rather than judging it by its own about page and design.
Triangulation
Confirming a factual point through independent sources that do not share a common origin. Three outlets repeating one press release are one source, not three.
Ad hominem
Attacking the arguer's character or circumstances instead of the argument. It only counts as a fallacy when the personal point is irrelevant to the claim's truth.
Straw man fallacy
Misrepresenting a position to make it easier to refute. It differs from ordinary disagreement in that the target is a distortion the opponent would not recognise.
False dilemma
Presenting two options as exhaustive when other possibilities exist. It is persuasive because it hides the middle range where most workable answers actually sit.
Slippery slope
Claiming that one step leads inevitably to an extreme outcome without establishing the intervening links. The argument becomes legitimate only if each transition is separately supported.
Hasty generalisation
Drawing a broad conclusion from a sample too small or too skewed to support it. It is the fallacy behind most confident claims built from personal experience alone.
Post hoc reasoning
Treating sequence as proof of cause because one event followed another. Ruling it out requires a mechanism and consideration of what else changed at the same time.
Circular reasoning
Assuming in the premises what the conclusion is supposed to establish, often disguised by restating the claim in different vocabulary. It feels convincing while proving nothing.
Appeal to inappropriate authority
Citing a figure whose expertise lies outside the question at issue. The move borrows credibility that does not apply to the domain being argued.
Bandwagon appeal
Treating widespread belief or adoption as evidence that a claim is true. Popularity can be relevant to questions about norms, but not to questions of fact.
Equivocation
Shifting the meaning of a key term between parts of an argument so that a conclusion appears to follow. Defining contested terms early is the standard defence against it.
Red herring
Introducing a distracting issue that draws attention from the point in dispute. It often survives in drafts as a genuinely interesting paragraph that answers a question no one asked.
Anecdotal evidence
Individual stories offered as proof of a general pattern. Anecdotes are powerful for illustration and unreliable for establishing frequency or cause.
Statistical significance misuse
Treating a reported result as proof of importance or size when it speaks only to how unlikely the pattern is under chance. Effect size and study design still have to be examined.