Introduction to Cryptography by Phil Zimmermann

From the man who brought us Pretty Good Privacy…

“No data security system is impenetrable. …You have to ask yourself if the information you are trying to protect is more valuable to your attacker than the cost of the attack. This should lead you to protect yourself from the cheapest attacks, while not worrying about the more expensive ones.”

This white paper was my first real encounter with cryptography back when it was considered a munition by the federal government. Zimmermann got into significant trouble when someone distributed his PGP code on the Internet. Here is his story of why he developed PGP in the first place and his subsequent Senate testimony.

Is There an Artificial God? by Douglas Adams

I’ve been a fan of Douglas Adams’ writing for many years. He is mostly known for his humorous science fiction but he was actually an important thinker and philosopher. A year after his death in 2001 his friends published several miscellaneous stories and essays as the book The Salmon of Doubt. As with many posthumous collections these materials were spotty and often unfinished. But there was a hidden gem—a transcript of a talk he gave at a scientific conference in 1998 entitled Is There an Artificial God? I think it stands as a wonderful testament to his humanism and intellect.

We build meta-systems above ourselves to fill in the space that we previously populated with an entity that was supposed to be the intentional designer…because we as a species design and create one and then allow ourselves to behave as if there [is] one—all sorts of things begin to happen that otherwise wouldn’t happen.

He ends with the wonderful “Four Ages of Sand” analogy. From sand we make glass and from glass we created telescopes, microscopes, computers, and fiberoptic networks.

Transcript (from

Audio File (marginal quality mp3)

More Douglas Adams quotes…