The Meaning of Symmetry
If an object shaped like this one were discovered in outer space, it would be proof of extraterrestrial life. Regardless of its size or material, and whether or not it looks like something we can identify, just the shape would be convincing evidence of life. Intuitively, just by looking at this shape, many people would agree. But why? The answer is in the meaning of symmetry. Symmetry is a natural phenomenon -- Lots of things, both living and not, are symmetrical in some way: So while there are a lot of symmetrical things in the natural world, there are also plenty that are not symmetrical. Why are some things symmetrical but not others? Things that are symmetrical are that way because the forces that have affected their design or their evolution are equal across their planes of symmetry. Things that are not symmetrical have been affected by unequal forces. This might make sense if we first look at an abstract definition of symmetry. This is actually a...
