For many years I have heard about 7.  Perhaps you have too.  Mostly I have heard (and became interested) in 7 as it related to memory. Most of what I had heard however came through “training” resources that I have grown to be increasingly suspicious of.  Some time ago I set out to find out what was behind 7.

An excellent resource regarding the mysterious number 7 is an old article written by Geroge A. Miller in 1956 entitled: The Magical Number Seven, Plus or Minus Two: Some Limits on our Capacity for Processing Information.  Miller has had an impressive career in psychology but is mostly known for the Seven Article which appeared in The Psychological Review of 1956.

In his article, Miller doesn’t present original research, but rather presents a summary of the early research into the capacity of people to transmit information (previously referred to as experiments in “absolute judgement”.) Miller first walks us through early experiments testing absolute judgements related to binary information. These involved testing subjects’ ability to make judgements about the pitch of sounds they heard, the loudness of sounds and the saltiness of a solution. In general, these studies showed that subjects could make accurate judgement on from 5 to 7 pitches or intensities and somewhat fewer levels of saltiness. He then compared these results to studies involving multidimensional inputs. The most interesting part of the article comes when Miller reviews the work done in immediate (short term) memory studies. He describes the research supporting both the ideas of “chunking” and “recoding”. Both of these notions have ramifications in the world of presentation design and development.

If you are one of those who are looking for mystical ways to design presentations in accordance with the laws of the universe, I submit Miller’s final paragraph his 1956 article:

And finally, what about the magical number seven? What about the seven wonders of the world, the seven seas, the seven deadly sins, the seven daughters of Atlas in the Pleiades, the seven ages of man, the seven levels of hell, the seven primary colors, the seven notes of the musical scale, and the seven days of the week? What about the seven-point rating scale, the seven categories for absolute judgment, the seven objects in the span of attention, and the seven digits in the span of immediate memory? For the present I propose to withhold judgment. Perhaps there is something deep and profound behind all these sevens, something just calling out for us to discover it. But I suspect that it is only a pernicious, Pythagorean coincidence.

Presentation Fact: Miller’s article is a worthwhile read for those serious about understanding the Magic of 7