tautologies
Self-evident truths stated
Tautologies is the plural of tautology—a statement that is true by virtue of its logical form, or a redundant repetition of meaning in different words.
In logic, A or not A is a tautology because it cannot be false.
In rhetoric, phrases like free gift or PIN number are tautologies because the second word repeats what the first already contains.
The term often carries a note of criticism: His speech was full of tautologies.
Redundant expression
- redundancyNeedless duplication
- repetitionAct of redoing
- verbosityUnnecessary word excess
- circumlocutionIndirect, wordy expression
wordiness · superfluity · reiteration · prolixity · rephrasing · restatement · belaboring · padding
Self-evident starting principle
- propositionStatement expressing a judgment
- theoremDemonstrated logical conclusion
- proofDemonstration of truth
- syllogismFormal deductive argument structure
validity · premise · conclusion · self-evident · identity · equivalence · biconditional · truism
Requiring no demonstration
- truismStatement needing no proof
- platitudeTrite, overused remark
- clichéOverused, unoriginal expression
- banalityTiresome lack of originality
bromide · commonplace · axiomatic · undeniable · evident · manifest · patent · clear
Alluding to itself
- closed-loopSystem with feedback control
- recursiveDefined in terms of itself
- self-justifyingDefending one's own actions
- bootstrappingSelf-starting without external input
pleonasm
Redundant expression
- redundancyNeedless duplication
- repetitionAct of redoing
- verbosityUnnecessary word excess
circumlocution · wordiness · superfluity · reiteration · prolixity · rephrasing · restatement · belaboring · padding · filler
axiom
Self-evident starting principle
- propositionStatement expressing a judgment
- theoremDemonstrated logical conclusion
- proofDemonstration of truth
syllogism · validity · premise · conclusion · self-evident · identity · equivalence · biconditional · truism · analytic
self-evident
Requiring no demonstration
- truismStatement needing no proof
- platitudeTrite, overused remark
- clichéOverused, unoriginal expression
banality · bromide · commonplace · axiomatic · undeniable · evident · manifest · patent · clear · incontrovertible
self-referential
Alluding to itself
- closed-loopSystem with feedback control
- recursiveDefined in terms of itself
- self-justifyingDefending one's own actions
tautologiescontradictions
Logically incompatible assertions
self-contradictions · paradoxes · absurdities · antinomies · fallacies