Argument from Ignorance (Fallacy of the Day)

By Peter Bokulich

Premise: I don’t know that it isn’t true.
Conclusion: Therefore it is true.

Premise: I don’t know how it could have happened.
Conclusion: It didn’t happen.

McCarthy: “Nothing in his file indicates that he is not a communist.”

Creationists: Scientists don’t know how Y evolved from X. Therefore evolution is false.
e.g.: http://creation.com/refuting-evolution-chapter-4-bird-evolution