When I was a child, the conversations around the dinner table in our house were especially vigorous and impassioned (as I soon learned when I discovered that I had to adjust my manner when I was a guest in other homes). When points of factual disagreement arose, this triggered the only grounds for being excused from the table in the middle of dinner: to look up the answer in the World Book Encyclopedia.
I remember vividly many occasions of triumphantly returning to the table, bulky blue volume in hand, to quote my vindication, and just as vividly the other occasions when I conceded defeat. I was wrong, and it says so right here in the World Book. The question of whether the World Book itself might be wrong seldom arose but was a recognized possibility.