3 is a more useful factor for many applications, including measurement for architecture, art, photography, etc. http://en.wikipedia.org/wiki/Rule_of_thirds http

3 is a more useful factor for many applications, including measurement for architecture, art, photography, etc. http://en.wikipedia.org/wiki/Rule_of_thirds http://en.wikipedia.org/wiki/Rule_of_thirds If I had to rank factors that would be most useful for measurement, I'd put 2, 3, and 4, and even 8 above 5.