When you want to fool the world, tell the truth.
Otto von Bismarck (born 1 April 1815, and All Fools Day), as quoted in American Speaker : Your Guide to Successful Speaking (1992) by Aram Bakshian.
The first of April, some do say Is set apart for All Fools' Day. But why the people call it so, nor I, nor they themselves, do know.
The first of April is the day we remember what we are the other 364 days of the year.