Argument from Omniscience

An argument from omniscience occurs when a person argues that "all people knows that" or "everyone believes that" in order to prove a point. This is fallacious as it is impossible to know what everyone is thinking, and that the existence of people who do not believe the same thing undermines their entire argument.

An example of an argument from omniscience would be saying a person saying "everyone knows pizza is the best food". This is fallacious because not only does not everyone believe pizza is the best food, but the speaker cannot know what everyone believes.