->''A = A''
-->-- ''The law of identity, the first of the three classical laws of thought''

[[ExactlyWhatItSaysOnTheTin An index of tropes having to do with logic.]] As you can see, many of these {{trope}}s detail ways in which writers can [[YouFailLogicForever fail at logic]]. For some reason, there aren't nearly as many about correct logic...

Compare IntelligenceTropes. Contrast MadnessTropes and EmotionTropes, which frequently defy logic in various ways.
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[[index]]
* LogicalFallacies
** AdHoc
** AdHominem (Attacking the person, not the argument.)
** AnecdotalFallacy
** AppealToAuthority
** AppealToConsequences
** AppealToFear
** AppealToFlattery
** AppealToForce
** AppealToIgnorance
** AppealToInherentNature
** AppealToNature
** AppealToNovelty
** AppealToObscurity
** AppealToPity
** AppealToPopularity
** AppealToRidicule
** AppealToTradition
** AppealToWealth
** AppealToWorseProblems
** ArgumentumAdNauseam
** ArgumentumAdLapidem
** AssociationFallacy
*** HitlerAteSugar
** BandwagonFallacy
** BeggingTheQuestion
** CabDriversFallacy
** ChewbaccaDefense
** CircularReasoning
** ConfirmationBias
** ConverseError
** ExtendedAnalogy
** FallacyFallacy
** FallacyOfComposition
** FallacyOfDivision
** FalseCause
** FalseDichotomy
** FourTermsFallacy
** FrozenAbstraction
** GamblersFallacy (Probability related failure of logical.)
** GoldenMeanFallacy
** HardWorkFallacy
** {{Hypostatization}}
** IrrelevantThesis
** LoadedWords
** ManyQuestionsFallacy
** MovingTheGoalposts
** NonSequiturFallacy
** NoTrueScotsman (Defining away inconvenient items; originally "No Scotsman puts sugar in his porridge!" "Angus [=MacGee=] does." "Ah, but then he's not a True Scotsman!")
** PerfectSolutionFallacy
** ProofByExamples
** ProsecutorsFallacy
** RetrospectiveDeterminism
** ReverseSlipperySlopeFallacy
** SemanticSlipperySlopeFallacy
** SharpshooterFallacy
** ShiftingTheBurdenOfProof
** SlipperySlopeFallacy
** SpecialPleading
** SpotlightFallacy
** StolenConcept
** StrawmanFallacy
** SunkCostFallacy
** TwoNegativePremises
** UndistributedMiddle
* ArkhamsRazor (In fiction, the oddest solution is probably correct)
* BatDeduction
* Catch22Dilemma
* EntertaininglyWrong (When somebody is wrong, for the right reasons)
* FridgeLogic (Logic problems that are only noticeable when you think a bit about them)
** {{Headscratchers}}
** PlotHole
* GivingUpOnLogic
* IfJesusThenAliens
* InsaneTrollLogic (When YouFailLogicForever is either intentional, or crosses over into PoesLaw.)
* JustifiedTrope (When use of a trope is made logical)
* LogicBomb
* MoonLogicPuzzle (A puzzle whose solution relies on overly narrow or unconventional interpretations of the available evidence)
* OccamsRazor (Explanations should avoid unnecessary complications.)
* PuffOfLogic
* RandomPasserbyAdvice
* ReasoningWithGod
* RightForTheWrongReasons (When you reach the correct conclusion, but by faulty logic.)
* SoundValidTrue (The three are not the same.)
* TheSpock
* TwoPlusTortureMakesFive
[[/index]]
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