My great-grandfather was a carpenter. Using just a few tools, he built tables, cupboards, and cabinets – one of which still graces my kitchen today. What was special about his work was its tangibility – the purpose behind everything he built was so that someone else could use it, and he could describe his profession by talking about particular techniques and tools, his workshop, or the objects he created.

In today’s twenty-first-century working world, we no longer have such down-to-earth objects. More and more often, we work with virtual information or must make sense of complex structures, abstract knowledge, or vast quantities of figures, data, and facts. The reason that we often struggle with this can be explained by one simple number: seven. Better stated: it can be explained by “Miller’s Magical Number.”

“Miller’s Magical Number” – Or, Why We Can Typically Only Remember Seven Things at a Time

One of the most frequently-cited topics in the field of psychology is a concept developed in 1956 by George A. Miller: “Miller’s Magical Number.” It is based on the assumption that human beings can only hold seven (plus/minus two) pieces, or “chunks,” of information at a time in their short-term memory. If we were computers, this would mean that we would have such a puny amount of RAM that it could hold an average of only seven items!

It is important to take this into consideration when we are trying to represent complex topics on posters.

The Three Most Important Rules for Visualization with Posters

If we adhere to the theory of Miller’s Magical Number, we can assume that we can best process information if we can visualize it by summarizing it into no more than seven, and preferably only five, “chunks.” To do this, we need to learn to cluster information and create logical hierarchies for it. When putting together a poster, it works best to think and work in these three levels: macro, meso, and micro.