Bare assertion fallacy

Name of fallacy Bare assertion fallacy
Type Deductive Logic Argument, Formal Argument
Description A premise in an argument is assumed to be true merely because it says that it is true.
Example Simon says that Jack eats ice cream
Simon says that Simon is not lying
Conclusion: Therefore, Jack eats ice cream
FormArgument of the form:
Fact 1: X claims statement A
Fact 2: X claims that X is not lying
Conclusion: Therefore, A is true
Treatment Dealt with by showing that the assumption to truth is not justified.