Informal Fallacies
Key Terms
Modus Ponens
Modus Tollens
Disjunctive Syllogism
Reduction Fallacy
Post Hoc Ergo Propter Hoc
Texas Sharpshooter Fallacy
Tautology
False Dilemma
Straw Man
Special Pleading
Slippery Slope
Weasel Words
Meaningless Jargon
Argument from Authority
Argument from Tradition
Bandwagoning
Ad Hominem Attack
Appeals to Emotion (Pity/Fear/Flattery)
Cherry Picking
Hasty Generalization
Hasty Conclusion
- Not logical
- Pseudo-reasoning (false reasoning)
- Unsound arguments
Fallacies of Evidence
- Or, what happens to public discourse when we forget to do proper research
- 4 types:
- Red Herring
- Cherry Picking
- Hasty Generalization
- Hasty Conclusion
Hasty Generalization
- Lack of sufficient information
- Insufficient data, but generalized conclusion is drawn anyway
Example
- In philosophy class, we’ve been studying some obstacles to discovering truth.
- Therefore, it is impossible to discover truth
Hasty Conclusion
- Sparse evidence, which may or may not be correct, is presented toward an argument
- Commonly used when one feels strongly about a position
- Claims are considered "hasty" when dissenting voices can easily counter with evidence
Examples
- Have you ever noticed how awesome the pyramids are? Some of the stones used to build them weigh more than 2 tons! And despite their size, their geometry is quite precise. It’s obvious that some kind of alien technology was required to build them!
Problems
- Any time there is insufficient evidence to draw a conclusion, the wrong conclusion can be drawn
What Logical Fallacies can you find? Video Clip