APPEAL TO AUTHORITY is sort of the reverse of ad hominem. Instead of disbelieving something because of the source, it's believing something because of the source. The "authority" might be a doctor, world leader, or other famous person. In other words, someone who would probably know more than you do.Since we can't know everything, we often rely on the judgments of authorities and experts. It's not a fallacy to assume that an expert is correct when they are discussing their area of expertise. For example, if your doctor tells you that your arm is broken, and shows you the X-ray, you can be pretty sure she knows what she's talking about.
But it is a fallacy to assume a source is infallible, or always right. Even doctors aren't perfect, which is why patients seek what is called a “second opinion."
The ad shown here is the kind of cigarette ad that used to appear in newspapers and magazines. How does it appeal to authority? Would doctors approve of cigarette smoking today?
Here are other examples of APPEAL TO AUTHORITY.
Thomas Jefferson said it, so it must be true.
It's in the bible, so it must be true.
Ayn Rand said it, so it must be true.
It also happens in advertising:
Johnny Depp is awesome.
He was eating Sugar Bomb Cereal in that commercial.
He said that Sugar Bomb Cereal was the best, healthiest cereal on the market.
Therefore, I am going to eat Sugar Bomb Cereal every day.
Johnny Depp might be an expert on acting. But is he a doctor or dietitian? He might be qualified to talk about making movies, but is he qualified to discuss the health benefits of breakfast cereal?
