What is symmetry and why is it important?
It’s important because it is one of the most essential tools in deciphering nature’s design, and it sits right at the intersection of science, art, and perceptual psychology. Our faces have almost precise bilateral symmetry, as do most animals around us. (If you reflect the left half in a mirror you obtain something that is almost identical to the right half.) Then there are objects that have rotational symmetry. Imagine passing a pin through the center of a six-cornered snowflake. Every time you rotate that snowflake by sixty degrees it looks exactly the same. Palindromes—such as “Madam, I’m Adam”—have a particular symmetry under back-to-front reading. Now think of wallpaper or a street of row houses: If you shift something by a certain distance in a certain direction you’ll see the same thing. That’s symmetry under translation. Many experiments have shown that symmetry is very important for perception. If you look at something that’s symmetric, you’re able to recognize it much faster