Trivia question: Why were local phone numbers originally seven digits long? The answer is that in the early days of local phone service, researchers found that seven digit numbers were about as long as most people could remember without forgetting or making errors. (One oft-quoted study on the “seven” topic is The Magical Number Seven, Plus or Minus Two: Some Limits on our Capacity for Processing Information by George A. Miller.)

If it’s hard to remember more than seven digits, how many complex concepts can we process and/or keep track of? I don’t think that research has been conducted, but a New York Times interview with Cristóbal Conde, president and C.E.O. of SunGard, suggests one solution: […]