Logical fallacies

• Types of Claims


  • Claim of fact
  • Claim of value
  • Claim of policy
• Logical Fallacies are errors in reasoning that invalidate an argument
• Logical Fallacies


  • False Dilemma
  • Appeal to Ignorance
  • Slippery Slope
  • Complex Questions
  • Appeal to Force
  • Appeal to Pity
  • Appeal to Consequence
  • Bandwagon
  • Attacking the Person
  • Appeal to Authority
  • Anonymous Authority
  • Hasty Generalization
  • False Analogy
  • Accident
  • Post Hoc
  • Wrong Direction
  • Complex Cause
  • Irrelevant Conclusion
  • Straw Man
  • Affirming the Consequent
  • Denying the Antecedent
  • Inconsistency
• False Dilemma


  Occurs when an arguer presents their argument as one of only two options despite the presence of multiple possibilities.
• Appeal to Ignorance


  Occurs when something is instantly concluded to be true just because it is not proven to be false, and vice versa.
• Slippery Slope


  Occurs when series of increasingly superficial and unacceptable consequences is drawn.

  Ex: if we ban computer shops, then students will not be able to do research. And if they do not have tools for research, these students will fail their subjects.
• Complex Questions


  Occurs when two or more points are rolled into one and the reader is expected to either accept or reject both at the same time, when one point may be satisfactory while the other is not.

  Ex: Have you stopped cheating on exams?
• Appeal to Force


  Occurs when threat, instead of reasoning, is used to argue.

  Ex: If you do not admit that evolution is not real, we will isolate you from the group.
• Appeal to Pity 


  Occurs when the element of pity is used instead of logical reasoning.

  Ex: Please do not fire me for being absent all month; I have a sick mother and a special child to support.
• Appeal to Consequences


  Occurs when unpleasant consequences of believing something are pointed out to show that the belief is false.

  Ex: You can't believe that colonialism is bad, because if it were, then we would not be civilized.
• Bandwagon 


  Occurs when an argument iw is considered to be valid because it is what the majority thinks.

  Ex: Most Filipinas want to have fair skin because they think they will look more beautiful. Therefore, having fair skin must be the real standard of beauty.
• Attacking the Person


  Occurs when someone tries to refuse an argument by attacking the character of a person instead of attacking the ideas of the argument.

  Ex: I cannot accept your argument because unlike me, you were not educated at Harvard University.
• Appeal to Authority


  Occurs when the argument quotes an expert who is not qualified in the particular subject matter.

  Ex: Bill Gates, co-founder of Microsoft, recommends the effective favric softening properties of Downy favric softener.
• Anonymous Authority


  The authority in question is not mentioned or named.

  Ex: Experts claim that eating peanuts causes pimples. 
• Hasty Generalization


  Occurs when a sample is not significsnt or enough to support a generalization about a population.

  Ex: Martha, the foreigner from France, is very impolite. French people are mean and rude.
• False Analogy


  Occurs when a writer assumes that two concepts that are similar in some ways are similar in other ways.

  Ex: Drugs are like massages; they make you feel good. 
• Accident


  Occurs when a general rule is applied to a situation, even when it should be an exception.

  Ex: Jaywalking is not allowed, so you shouldn't do that even if you were being chased by a terrorist.
• Post Hoc


  Occurs when the arguer claims that since event A happened before event B, A is the cause of B.

  Ex: Dina saw a black cat when they went home. Along the way, they crashed into a tree. The black cat must be the reason.
• Wrong Direction


  Occurs when the direction between cause and effect is reversed.

  Ex: Liver damage leads to alcoholism.
• Complex Cause 


  Occurs when the explanation for an event is reduced to one thing when there are other factors which also contributed to the event.

  Ex: We were not able to solve the problem because of limited tine, even though all other groups were able to do so 
• Irrelevant Conclusion


  Occurs when an Argument which is supoosed to prove somehting concludes something different instead.

  Ex: we must supoort the fight for gender equality between men and women. Women have suffered enough violence at home. Violence against women must be stopped.
• Straw Man


  Occurs when the positiin of the opposition is twisted so that it is easier to refute.

  Ex: Opponent: we should relax the law governing the allowed smoking areas in the city.

  Fallacy: we should not do so because the number of smokes might increase.
• Affirming the Consequent


  Any argument of the form: IF A IS TRUE THEN B IS TRUE, IF B IS TRUE, THEREFORE A IS TRUE.

  Ex: If you are drinking wine then you have a problem. Therefore, if you have a problem, you are drinking wine.
• Denying the Antecedent


  Any argument with the form of: IF A IS TRUE THEN B IS TRUE, IF A NOT TRUE THEN B IS NOT TRUE.

  Ex: If youa re drinking wine, you have a problem. Therefore, if you are not drinking wine, you do not have a problem.  
• Inconsistency


  Occurs when arguments contradict one another.

  Ex: Frank is older than Jake, Jake is older than Noli, and Noli is older than Frank.