Shamelessly pilfered from another site Enjoy!
The forums have in many ways become plagued by terrible argument. People who (I am sure) are perfectly normal IRL, seem to lose their way in any from of online debate. I have been watching this and have compiled a list of common mistakes. Please refer to it whenever necessary or even just when you have some doubt over your posting.
So without further ado:
You are wrong because:
1. Amazingly Bad Analogy
Example: You can train a dog to fetch a stick. Therefore, you can train a potato to dance.
2. Faulty Cause And Effect
Example: On the basis of my observations, wearing huge pants makes you fat.
3. I Am The World
Example: I don't listen to country music. Therefore, country music is not popular.
4. Ignoring Everything Science Knows About The Brain
Example: People choose to be obese / gay / alcoholic because they enjoy the lifestyle.
5. The Few Are The Same As The Whole
Example: Some South Africans are animal rights activists. Some South Africans wear fur coats. Therefore, South Africans are hypocrites.
6. Generalising From Self
Example: I am a liar. Therefore, I don't believe what you are saying.
7. Argument By Bizarre Definition
Example: He is not a criminal. He just does stuff that is against the law.
8. Total Logical Disconnect
Example: I enjoy pasta because my house is made of bricks.
9. Judging Things Without Comparison To Alternatives
Example: I don't invest in Unit Trusts. There is too much risk.
10. Anything You Don't Do Is Easy To Understand
Example: If you have the right tools, how hard could it be to generate nuclear fission at home?
11. Ignorance Of Statistics
Example: I am putting ALL my money on the Lottery this week because the jackpot is so big.
12. Ignoring The Downside Risk
Example: I know that Bungee Jumping could kill me, but it is 3 seconds of great fun!
13. Substituting Famous Quotes For Common Sense
Example: Remember: "All good things come to him who waits". So don't bother looking for a job.
14. Irrelevant Comparisons
Example: A hundred Rand is a good price for a toaster, compared to buying a Ferrari.
15. Circular Reasoning
Example: I am correct because I am smarter than you. And I must be smarter than you because I am correct.
16. Incompleteness As Proof Of Defect
Example: Your theory of gravity does not address the question of why there are no unicorns, so it must be wrong.
17. Ignoring The Advice Of Experts Without Good Reason
Example: Sure, the experts think you shouldn't ride a bicycle into the eye of a hurricane, but I have my own theory.
18. Following The Advice Of Known Idiots
Example: Uncle Billy says pork makes you smarter. That's good enough for me!
19. Reaching Bizarre Conclusions Without Any Information
Example: The car wont start. I am certain the spark plugs have been stolen by rogue clowns.
20. Faulty Pattern Recognition
Example: His last six wives were murdered mysteriously. I hope to wife number 7.
21. Failure To Recognise What's Important
Example: My house is on Fire! Quick, call the post office and tell them to hold my mail!
22. Unclear On The Concept OF Sunk Costs
Example: We've spent millions developing a water-powered pogo stick. We cant stop investing now or it will all be wasted.
23. Over-application Of Occam's Razor
[which says that the simplest explanation is usually right]
Example: The simplest explanation for the moon landings is that they were hoaxes.
24. Ignoring All Anecdotal Evidence
Example: I always get hives immediately after eating strawberries. But without a scientifically controlled experiment, it is not reliable data. So I continue to eat strawberries every day, since I cant tell if they cause hives.
25. Inability To Understand That Some Things Have Multiple Causes
Example: The Beatles were popular for one reason only: They were good singers.
26. Judging The Whole By One Of Its Characteristics
Example: The sun causes sunburn. Therefore the planet would be better off without the sun.
27. Blinding Flashes Of The Obvious
Example: If everyone had more money, we could eliminate poverty.
28. Blaming The Tool
Example: I bought an encyclopaedia but I am still stupid. This encyclopaedia must be defective.
29. Hallucination Of Reality
Example: I got my facts from a talking tree
30. Taking Things To Their Illogical Conclusion
Example: If you let your hairdresser cut your hair, the next thing you know she will be chopping off your limbs!
31. Failure To Understand Why Rules Don't Have Exceptions
Example: It should be legal to shoplift, as long as you don't take enough to hurt the company's earnings.
32. Proof By Lack Of Evidence
Example: I have never seen you drunk, so you must be one of those Amish people.