Appeal to Authority
An expert's word is not proof by itself.
What it is
An appeal to authority treats an expert’s statement as settled proof. Experts are evidence, not conclusions.
The flaw appears when the authority is irrelevant to the topic, unnamed, or simply cited instead of any real evidence. A genuine expert on the exact topic, giving reasons, is a different story.
An LSAT-style example
This example is original. It is not a real LSAT question.
A famous actor says this vitamin boosts energy. So the vitamin must boost energy.
The flaw: Fame is not expertise in nutrition. The argument gives no evidence about the vitamin itself.
How to spot it on test day
- Ask: is this person an expert in this specific field?
- Ask: are they giving reasons, or just lending their name?
- Celebrity, wealth, and job titles are not expertise.
The right answer vs. the trap
The right answer
The correct answer says the argument relies on an authority who lacks relevant expertise, or cites authority in place of evidence.
The trap
The trap may say the argument is fine because the person is accomplished. Accomplishment in one field does not transfer to another.
Find your weak flaws
The free diagnostic scores every question type, including flaw questions, and shows exactly where you are losing points.