Argument from Ignorance

An argument from ignorance is a logical fallacy that says that something is true because it has not been proven false. Someone using an argument from ignorance often uses the fact something has not been disproven to put the burden of proof on their opposition. This is especially fallacious in discussions about things that are unknowable or impossible to prove.

An example of an argument from ignorance would be saying that because no one has proven that unicorns do not exist, then unicorns must exist.