"Whatever you do will be insignificant, but it is very important that you do it."

If you want to know what Phil Zimmermann’s about, this quote from Mahatma Gandhi might be a good place to start. Zimmermann picked it up during his earlier days as an anti-nuclear activist, during which he’d once been arrested along with astronomer Carl Sagan, actor Martin Sheen, and Pentagon Papers-leaker Daniel Ellsberg. And when, in 1991, he released Pretty Good Privacy, an encryption program for the increasingly popular technology known as electronic mail, the quote was on his mind. It found its way into a section titled “Why I Wrote PGP” as a humble declaration of purpose: a single action may not change the world, but that doesn't absolve individuals of the responsibility of acting.