tautology
C1-C2formal, academic, literary, critical
Definition
Meaning
A statement that repeats the same idea using different words, resulting in redundant meaning.
In logic and rhetoric: a statement that is true by its logical form alone (e.g., 'A = A'). More broadly: any unnecessary repetition in expression.
Linguistics
Semantic Notes
Carries a negative connotation of being pointless, empty, or lacking in informative value.
Dialectal Variation
British vs American Usage
Differences
No significant lexical or semantic differences. Slightly more common in British academic/philosophical writing.
Connotations
Equally pejorative in both varieties.
Frequency
Low frequency in everyday speech; higher in academic/logical contexts.
Vocabulary
Collocations
Grammar
Valency Patterns
to be a tautologyto smack of tautologyto verge on tautologyto contain a tautologyVocabulary
Synonyms
Strong
Neutral
Weak
Vocabulary
Antonyms
Phrases
Idioms & Phrases
- “(to be) a tautology in terms”
- “true by tautology”
Usage
Context Usage
Business
Rare. May appear in critiques of marketing buzzwords or circular corporate mission statements.
Academic
Common in philosophy, logic, linguistics, literary criticism, and rhetoric to denote empty or circular propositions.
Everyday
Very rare. Used self-consciously to criticise wordy, repetitive speech or writing.
Technical
Core term in formal logic for a compound statement that is true for all possible truth values of its components.
Examples
By Part of Speech
noun
British English
- The phrase 'free gift' is a classic tautology, as a gift is inherently free.
- His entire argument collapsed into a mere tautology, proving nothing.
American English
- Defining 'happiness' as 'the state of being happy' is a useless tautology.
- The policy statement was criticized for its tautology and lack of concrete detail.
Examples
By CEFR Level
- The reviewer pointed out the tautology in the author's description of a 'round circle'.
- Saying 'they arrived one after the other in succession' is a bit of a tautology.
- The politician's defence was a tautology: he asserted the policy was good because it was beneficial.
- In predicate logic, the formula 'P ∨ ¬P' is a tautology, always true regardless of P's truth value.
Learning
Memory Aids
Mnemonic
Think: 'TAUTology = Talking Again, Unnecessarily, Together.' It's saying the same thing twice, tied up in a loop.
Conceptual Metaphor
LANGUAGE IS A CONTAINER (for meaning); a tautology is an EMPTY CONTAINER or a CONTAINER that holds the same thing twice.
Watch out
Common Pitfalls
Translation Traps (for Russian speakers)
- Avoid translating directly as 'тавтология' in casual contexts; it's a highly specialised loanword in Russian, used almost exclusively in academic criticism.
Common Mistakes
- Confusing with 'taxonomy'.
- Using it to mean simply 'a long, boring speech'.
- Misspelling as 'tautalogy' or 'tautology'.
- Overusing in non-academic contexts where 'repetition' or 'redundancy' would suffice.
Practice
Quiz
In which field is 'tautology' a precise, non-pejorative technical term?
FAQ
Frequently Asked Questions
A tautology is redundant in meaning or logic (e.g., 'A is A'). A pleonasm is a stylistic redundancy of words (e.g., 'I saw it with my own eyes'). All tautologies are pleonastic, but not all pleonasms are logical tautologies.
In everyday communication and argumentation, yes—it is seen as empty or circular. However, in formal logic and mathematics, tautologies are fundamental, truth-preserving structures and are not criticised.
The sentence 'It is what it is' is a common conversational tautology. It offers no new information about what 'it' actually is.
A contradiction—a statement that is false by its logical form alone (e.g., 'A and not A').
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