The Back to the Future actor, 63, was seen flashing a peace sign to fans as he spent time at the Chiltern Firehouse in London ...

Business Insider spoke with Tim Marshall, author of "Worth Dying For: The Power and Politics of Flags" about how the swastika was a symbol of peace until Hitler and the Nazi party changed its meaning.

The index and the middle finger formed in the shape of a V — the universal sign for peace. Has anyone in the history of Lawrence ever flashed the peace sign more often than Rob Blank?

Forty-seven of them, or 80 percent, spontaneously made the peace sign. When asked why they did it, one woman said it "just popped up" in her mind. Another said she always makes the peace sign in ...