Jim Fact

A fact that is plausible, interesting and true in all details except for one critical point.

Jim: Did you know chicken pox derives from a strain of smallpox?

John: Wow, really?

Jim: Yeah yeah! Isn't that interesting...

John, after checking the internet: No they aren't! Shenanigans! They aren't even in the same virus family! That's a Jim Fact if I ever heard one!