Why is it so easy to say something in an e-mail or on a blog without having the slightest idea how it will come across to the reader? Turns out there is “a design flaw inherent in the interface between the brain’s social circuitry and the online world. In face-to-face interaction, the brain reads a continual cascade of emotional signs and social cues, instantaneously using them to guide our next move so that the encounter goes well. … And in e-mail there are no channels for voice, facial expression or other cues from the person who will receive what we say.”