Logical thinking 7 Appeal to authority

Authority can be convincing, but is it infallible?

Discuss the role of authority and experts in creating a logical argument

Warm Up: 

Take a look at this advertisement from the 1930's:

It says:

20,679 physicians say Luckies are less irritating. Toasting removes dangerous irritants that cause throat irritation and coughing.

How much should we trust these physicians? Why do you think they said such a thing?


Thinking logically, we can call experts into question. What kind of things can you call into question to weaken a claim from authority?

Some phrases for evaluating authority are shown below. Using softer language to do this is more suitable. Why? We can use phrases like:

Personally, I think it's important that we...     ...consider (the reason for...)
I feel the need to... ...question (why...)
I suppose we can... ...take a look at (this a little more deeply.)



Below are some claims by authority. Consider how valid they are, and think of any questions that you can ask to weaken the argument. Some of these may be perfectly valid, while others are partially valid or completely invalid.

  1. Scientists state that nicotine improves brain function.
  2. Doctors have linked peptic ulcers to the stress of modern life.
  3. A study on rats, funded by the Sugar Association found adverse effects of consuming an artificial sweetener. The manufacturer responded by sponsoring its own team of experts to refute the study.
  4. According to Google's reports, their self-driving cars are 100% safe.