Humorous true story -
My Wife was just watching a BBC America nature/science show about island people living within their resource base and I commented, just look at Easter Island to see what happens when they don't. She responded by reminding me when she and our son were watching Carl Sagan's COSMOS years ago on PBS. All of a sudden, my son turned to her with a shocked look on his face and asked her if Carl Sagan knew more than Daddy? Poof! My credibility went down the drain!
A few years later, I got a Far Side calendar for Xmas and one day I told my son, who was really into dinosaurs at the time, that I knew what killed the dinosaurs and showed him the Far Side cartoon of juvenile dinosaurs smoking cigarettes at the base of a cliff. He just looked at me with a "I thought you were smart" look. At least he never started smoking!