From Andres Gomez Emilsson on Facebook:

A friend of mine (Taru the Qualiaphile from Finland) made this tool to train your ability to identify and name wallpaper symmetry groups.

For example, the one I posted here is X which means that it's a symmetry group that has one "reflection" () element and one "glide element" (X). The reflection is the normal mirroring we all know and love. "Glide" mean "translation and reflection". This picture has both of those elements, and nothing else, so it is called *X. There are 17 symmetries like this (their names also pictured here).

This is a very useful skill to have to be able to report your visit to spiritual places and beautiful architecture such as temples and churches (which are full of wallpaper symmetries) as well as being able to describe the phenomenology of exotic states of consciousness. With this website you can train yourself to notice and name them quickly, and thus gain this precious skill!

Of course interacting with this tool will ultimately change how you see the world - your visual system can get better at quickly rendering scenes when there are vague hints of symmetries because it can then find the wallpaper symmetry group that best approximates it.

Play with it for 15 minutes and a "Tetris Effect" begins to happen. You might have unusually symmetrical dreams that night 🙂

taru-u.github.io/apps/symmetry…