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False cause

(Also known as post hoc, from post hoc ergo propter hoc, a Latin expression meaning "after this, therefore because of this")

As a writer, you want to ensure that your readers will follow your arguments easily and find them convincing. To build sound arguments, you need to be aware of common errors (or fallacies) in logic and be careful to avoid them. There are many types of logical fallacies. In this article, we'll look at false cause.

This error in logic is very common. When two events occur one after the other, the writer assumes that the first event caused the second, without enough evidence.

A lot of superstitions are based on this kind of reasoning:

"My friend gave me a crystal charm, and both times I wore it, I won at cards. But the time I forgot it at home, I lost. I have to remember to wear that crystal if I want to win."

But this type of reasoning is not found only in superstitions:

Two employees attended the weekend conference. They were both sick afterwards. The food served at the conference must have been bad.

In this example, although the employees' illness may have been caused by food poisoning at the conference, there is not enough evidence to draw a conclusion. The fact that the sickness occurred after the conference does not prove that something at the conference was the cause.