"A straight line is said to have been cut in extreme and mean ratio when, as the whole line is to the greater segment, so is the greater to the less." -- Euclid, geometer, Elements, Book VI, Definition 3
Science Daily: Mystery of Golden Ratio Explained.
Adrian Bejan, professor of mechanical engineering at Duke's Pratt School of Engineering, thinks he knows why the golden ratio pops up everywhere: the eyes scan an image the fastest when it is shaped as a golden-ratio rectangle.
The natural design that connects vision and cognition ...