"The natural flow of technology tends to move in the direction of making surveillance easier, and the ability of computers to track us doubles every eighteen months." (Wikipedia)
Zimmermann’s Law: PGP inventor and Silent Circle co-founder Phil Zimmermann on the surveillance society, GigaOM, 2013-08-11
E-mail's Big Privacy Problem: Q&A With Silent Circle Co-Founder Phil Zimmermann, Forbes, 2013-08-09