Sometimes people on TV and the internet talk about “experts.” Experts say this, experts say that. Experts are always saying things.

Some good questions to ask about experts are, “Who are these experts?” and “How do they know all that stuff?”* A good thing to remember about experts is that they are people just like you. Even though they know more than you know about giraffes or airplanes or cancer, sometimes the things they say are wrong.

But when a lot of experts get together, as a group they are wrong (about giraffes, airplanes, cancer, whatever) less often than a group of non-experts.

If you want to be a good guesser, you have to look for patterns. If one cancer expert bets you fifty dollars that jogging cures cancer, you should probably ask a bunch of other cancer experts what they think before you reach for your wallet.

Sometimes a lone expert comes along and blows away all the other experts with a new idea that sounds completely insane, but that’s pretty rare.

*An honest expert will be able to tell you exactly how she knows all that stuff.