Especially if they are family members. I try to just smile and shrug it off, but it's very frustrating at times. I really have to bite my lip or contain my anger sometimes. The following are actual comments.
"The Earth isn't that old. No more than 10,000 years."
"We never went to the moon...
I enjoy reading about almost any battle or commander: Civil wars (US, Russian, English, etc), Franco-Prussian, Peloponnesian, Crimean, Hundred Years War, Thirty Years War, WW I & II, Succession wars, etc. etc.