tautology
Saying it twice
A tautology is a statement that is true by definition or repeats the same idea in different words: A bachelor is an unmarried man.
In logic, tautologies are formulas true under all interpretations.
In everyday speech, tautology often criticizes redundant phrasing: free gift, advance planning, true facts.
The adjective is tautological.
Redundant expression
- redundancyNeedless duplication
- repetitionAct of redoing
- verbosityUnnecessary word excess
- circumlocutionIndirect, wordy expression
prolixity · wordiness · tautologous · restatement · reiteration · belaboring
Of logical statements
- logicalBased on valid reasoning
- validityQuality of being sound
- disjunctionState of being apart
- conjunctionWord joining clauses together
negation · self-evident · boolean · equivalence · biconditional · axiom · theorem · proof
Alluding to itself
- vacuousEmpty of content
- uninformativeConveying no knowledge
- truismStatement needing no proof
- obviousEasily perceived, unmistakable
Examining by decomposition
- WittgensteinPhilosopher of language limits
- linguisticConcerning language study
- conceptualOf or relating to ideas
- epistemologyTheory of knowledge
pleonasm
Redundant expression
- redundancyNeedless duplication
- repetitionAct of redoing
- verbosityUnnecessary word excess
circumlocution · prolixity · wordiness · tautologous · restatement · reiteration · belaboring
propositional
Of logical statements
- logicalBased on valid reasoning
- validityQuality of being sound
- disjunctionState of being apart
conjunction · negation · self-evident · boolean · equivalence · biconditional · axiom · theorem · proof · deduction
self-referential
Alluding to itself
- vacuousEmpty of content
- uninformativeConveying no knowledge
- truismStatement needing no proof
obvious · self-evident · meaningless · definitional · unfalsifiable
analytic
Examining by decomposition
- WittgensteinPhilosopher of language limits
- linguisticConcerning language study
- conceptualOf or relating to ideas
- repetitionagain, repeat, repeated, recurring, recurrence
- logicpremise, premises, conclusion, conclusions, inference
- philosophy termstruth, reason, knowledge, wisdom, logic
- Propositionsstatement, assertion, claim, premise, conclusion
- Redundanciespleonasm, redundancy, redundant phrase, added bonus, free gift
- Self-referenceself-reference, self-referential, recursion, recursive, meta
tautologyconciseness
Quality of being brief
brevity · succinctness · terseness · pithiness · laconicism
tautologycontradiction
Opposing claims, incompatible together
self-contradiction · logical contradiction · paradox · antinomy · inconsistency