Frequenter Mendax

From Latin Frequenter meaning "often/in-great-numbers" and Mendax meaning "false/deceptive". The phrase is used to describe things that have been proven wrong so many times that they are no longer worth debating or considering scientifically.

Person 1: "Why don't scientists fight more flat earthers?"
Person 2: "Because the flat earth theory is frequenter mendax; its not worth disproving what has been disproved over and over again."

Mendax

A condition when someone knew the truth, but insisted to told the untruth statements.
Acknowledge the untruth.

A: Isaac Newton discovered gravity phenomenon when he was under a banana tree.
B: Of course, greetings from Binjai
C: Mendax!