This tutoria explores symmetry as an element of composition.
Source: Image of Starry Night, Vincent van Gogh, Public Domain, http://en.wikipedia.org/wiki/File:Van_Gogh_-_Starry_Night_-_Google_Art_Project.jpg; Image of Visioni Simultanee, Umberto Boccioni, Public Domain, http://en.wikipedia.org/wiki/File:Umberto_Boccioni_-_Visioni_simultanee.jpg
The quality of having exactly similar parts facing each other across an axis.
An imaginary line that divides an object.
When elements of a composition carry equal weight, or create harmony. A composition can be asymmetrical and balanced at the same time.
Lack of equivalence or similarity between parts.
When two halves of something are exactly the same.
The illusion of movement in a composition.