Our bodies are programmed to consume fat and sugars because they're rare in nature... In the same way, we're biologically programmed to be attentive to things that stimulate: content that is gross, violent, or sexual and that gossip which is humiliating, embarrassing, or offensive. If we're not careful, we're going to develop the psychological equivalent of obesity. We'll find ourselves consuming content that is least beneficial for ourselves or society as a whole. Just as the factory farming system that produces and delivers our food shapes what we eat, the dynamics of our media shape what information we consume.

speech at the 2009 Web 2.0 Expo