Why We Are So Fascinated by Symmetry: Interview with Per Mollerup

How would you explain symmetry?

“Symmetry is valuable repetition, but the purpose of symmetry can be of different kinds. It can, for instance, be aesthetic: meaning, people find symmetry beautiful. Aesthetic is what people usually think of when we talk about symmetry. But there are other aspects that I find far more important, like the practical aspect and the natural one. These two aspects are more interesting than aesthetics, which is quickly addressed.

Practical symmetry can also be termed economic symmetry. When you draw something symmetrical, it’s already complete when you’ve drawn the first half. Before computers, furniture architects often just drew half a chair. They would show it to the manufacturer, who well understood what the other half would look like. It’s also cheaper to produce a chair that is identical on both sides.

The entire industry is built on modular repetitions, and modules are nothing but symmetry in two or three dimensions. Symmetry, symmetry, symmetry. There’s no construction without symmetry. You might create an asymmetrical house, but the bricks will be symmetrical. You won’t find a place where there isn’t enormous saving associated with symmetry. It’s simply the basis of all industry.

Natural symmetry is about what’s determined by nature. What’s up and what’s down is determined by gravity. What’s front and back is determined by movement. Finally, there’s sideways – and nothing determines that. Hence, one side often mirrors the other. That’s why we constantly have left/right symmetry and very rarely up/down symmetry. It correlates with the fact that all forward-moving animals are constructed the same way. We also design forward-moving vehicles that way.

The main rule for all design is that if there’s no reason for anything else, it becomes symmetrical. When you break the natural symmetry, it’s because there’s a reason for it. For example, there’s a reason that the driver doesn’t sit in the middle of a car. They need to get in and out of the car and be able to stick their head out the window to grab a ticket.”

How do humans perceive symmetry?

“We perceive it all the time. For example, we prefer faces that have some symmetry. If they are perfectly symmetrical, there’s something boring about them, and if they are very asymmetrical, we think they are ugly.

Asymmetry is an exciting part of the narrative about symmetry. Your hands are asymmetrical individually but together they form a symmetrical pair. The same goes for your ears, eyes, and feet. They are asymmetrical, but they exist in symmetrical pairs. Something similar applies to design and architecture. There are two kinds of symmetry: One where the individual thing is symmetrical and one where two or more things are symmetrical as a set.”

What’s the historical perspective of symmetry?

“All the historical styles up until modernism had symmetry on the agenda. People made completely symmetrical houses. Not just the front, not just the facade, but also the content. When people talk about symmetry in architecture, they always think about facades, not the plan. It’s far rarer to have a symmetrical plan. An example of this is the now-demolished Palladium cinema in Copenhagen. When you entered, there was the same thing on the right as on the left.”

What happens when things are not symmetrical?

“A great architecture critic, Christopher Alexander, once said that architecture is about making a lot of small, individual things and then assembling them into a complex whole. Symmetry is simplifications that can be assembled into an asymmetrical whole. If you look at well-known architecture around the world, you can see that an asymmetrical whole with lots of symmetrical parts is a good recipe for a lot of houses. It’s not a cookbook recipe where you can just say, ‘we’ll do it this way’. But if you look at the finished result, it fits a terrible lot of houses.

Most symmetry just arises. There’s nobody saying they want to make something symmetrical. It arises because it’s a natural thing. If you make something with your hand, it might turn out symmetrical if there’s no reason for anything else. Highly likely.”

Are you constantly aware of symmetry?

“Not at all, no more than anyone else. Now, of course, I am because I know the different categories. When I see Our Saviour’s Church, I see that the spire is conically screw-symmetrical and right-handed. I see that now. I can no longer see a tower with a spiral staircase without thinking about what it is.”