This is a biggie. I like the famous example of a Sophist who once had the following dialogue with a Victim.
S: Is that your dog?
S: Is he a father?
S: Then that dog is your father. And do you beat that dog?
S: Then you beat your father.
Do you know what the mistake is here? Anyone can see there is something fishy, but can you nail down what it is, exactly? If not, then you should go to the library or the bookstore [or Mises.org and do a search for free pdfs] and find a book on simple logic that speaks to you, and learn something.
2. Getting distracted by emotions.
If you are a dog lover, and you read that the Victim beats his dog, did you suddenly feel "Go get him, Sophist"? Did you feel satisfaction that the Victim was made to look like a fool, being told that he beats his father?
Well, that's perfectly OK, but you have to watch out for one thing. Don't let your emotion sway you into thinking the Sophist had a good logical case. Keep the two things separate. That Victim really deserved it, but the Sophist was pulling a fast one.
I'll sometimes be discussing something with a person, making a logical case for something or other. Then I'll mistakenly mention a word that is highly emotionally charged and, like a hungry dog seeing a juicy steak, the person will forget everything else and just get all worked up. Moral of the story: Try and steer clear of highly charged words. Also, don't let them distract you.
3. Blind faith.
For some reason we think that the schools we are literally forced to attend [remember truant officers?] feed us the truth. And that if all the Television shows say something, it must be true.
Thus we accept many things as true without thinking about them at all, just because everyone tells us it is so. I remember thinking in 2006 that prices of houses always go up. Always. Where did I get that info? Because "everybody knew it". I remember feeling very sophisticated and intelligent having an opinion on economic matters. But had you asked me, "Why must they always go up?" I of course would have had no answer.
4. Responding to personal attacks.
When someone called me names on various forums, I used to reply to them in kind, as they justly deserved. But the highly emotional atmosphere that created distracted people from concentrating on the case I was actually trying to make. When I reread those posts, I have a hard time following what I myself wrote, so lost is the actual content in the forest of insults.
When faced with insults now, I just man up and respond only to the reasoning, as if the personal insults to me were never written. And oddly enough, I feel better after.
5. Writing style.
I personally like to write very simply, with simple examples and small words. I think that is the appeal of this humble blog. Very smart people have told me that the really earth shattering discoveries and ideas they had were always very simple, always expressible in simple language. A wise man once said "If you can't explain it in simple words, you don't really understand it, either."
Imagine my surprise when someone wrote about a post of mine that I should use bigger words! Later I found that this person, though well read, had big holes in his understanding. Makes you wonder.
Rest assured that anything Obama and Democrats and 99% of the Republicans say about the economy will be wrong, as is anything you read in your local paper, but for the dry facts. Which means you will have plenty of chances to practice the game of "Spot the Mistake".
I think it's important to be able to show exactly why they are wrong. And if you can't, that means you have to read up.
7. Peter Schiff.
Here is someone that separates the men from the boys.
If you read his stuff, watch his videos, listen to his podcasts and radio shows, you will note that he excels in all six of the above.
Some people don't like him. His confidence and brashness strikes them as arrogance.
But watch some of the Youtubes of the way he is viciously attacked and laughed at, and the humility and class with which he handles himself in those situations.
And those who like the big word over the little word dislike him, too. But I think that says something about the critics, not about him.
You can learn a lot from Peter Schiff.