Speglade

Symmetry (from Greek συμμετρία symmetria "agreement in dimensions, due proportion, arrangement") has two meanings. The first is a vague sense of harmonious and beautiful proportion and balance. The second is an exact mathematical "patterned self-similarity" that can be demonstrated with the rules of a formal system, such as geometry or physics.

Although these two meanings of "symmetry" can sometimes be told apart, they are related, so they are here discussed together.

Wikipedia