What is the Most Human Level of Complexity?

One of the goals of continuous improvement, or the management of any enterprise, always seems to involve reducing complexity. It is almost an article of faith that simplicity equals beauty and goodness. I’ve always had a vague nagging doubt about this. While things shouldn’t be complicated, it seems a certain amount of complexity is not only unavoidable, but necessary, and possibly even desirable. When a tradeoff of options is always in favor of simplicity, it feels to me that we are lose some curious and possibly beautiful things that complexity brings. This becomes a highly subjective debate, one that must ultimately be solved by customer-driven evidence-based utility in the case of business, or individual aesthetic preference in the case of art.

Because of my ambivalence towards making complexity the villain, it was exciting to learn that there is a non-zero amount of complexity that the human brain prefers. When optical arousal by computer-generated visual design is compared, an intermediate amount of complexity, and not the lest, is automatically the most stimulating to the brain. This is a relevant quote from E.O. Wilson’s book The Social Conquest of Earth

[…] the brain is most aroused by patterns in which there is about a 20 percent redundancy of elements or put roughly, the amount of complexity found in a simple maze, or two turns of a logarithmic spiral, or an asymmetric cross.

The middle of the three images below is not the least complex, yet it is the most appealing to our brains. A process that grows up from human happenstance may look like the mess on the right. The robotic and rational pursuit of continuous improvement may result in a solution that looks like the image on the left. But one that balances respect for humanity with continuous improvement looks like the middle option.

Wilson goes on to observe that this intermediate level of complexity is shared widely across art forms such as friezes, grillwork, colophons, logographs flag designs, the glyphs of ancient Middle East and Mesoamerica, as well as the pictographs and letters of modern Asian languages. Our brains seem to settle on the same level of complexity as being attractive across time, regions, cultures and mode of expression. Wilson speculates, “The source of the principle may be that this amount of complexity is the most that the brain can process in a single glance” implying that our minds do not prefer the least amount of complexity, nor the most extreme amount, but the most that the brain can process.

Visual art, like language, is intended to capture our attention and communicate something. This requires an appropriate level of complexity. When we redesign our processes with an aim to simplify them, we should also ask whether “less is more” when it comes to complexity, or whether there is an appropriate intermediate level of complexity which best engages our brains. Tasks that are too easy are boring. Tasks that are too complicated are frustrating. Common sense tells us that we do our best work in the middle ground. Does this then require us to leave a little bit of complexity in any process that we design for humans? A healthy little bit of challenge and struggle which keeps people thinking? A process that is so streamlined as to embody “simplicity itself” may in fact be barren of potential for future improvement. What is the process equivalent of the “20 percent redundancy of elements” noted in visual designs that most appeal to us?

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