1) Informal fallacy 
A falsism is a claim that is clearly and self-evidently wrong. A falsism is usually used merely as a reminder or as a rhetorical or literary device. An example is `pigs can fly.` It is the opposite of truism. A falsism is similar to, though not the same as, a fallacy. ...
• (n.) That which is evidently false; an assertion or statement the falsity of which is plainly apparent; -- opposed to truism.
Fals'ism noun That which is evidently false; an assertion or statement the falsity of which is plainly apparent; -- opposed to truism .