What’s the characteristic of most attractive faces?

Picture the most beautiful face you have ever seen. Then ask yourself what it is about that face that makes it so lovely. That question may be difficult to answer. After all, beauty is in the eye of the beholder. But is it possible to explain the beauty of a human face using math?
   According to many scholars throughout history, the answer could be yes. Most very attractive faces have proportions consistent with what is known as the "golden ratio." This ratio can best be understood by thinking of it as a rectangle. In a golden rectangle, the long side is 1.618 times longer than the short side. Therefore, the value of the golden ratio is equal to 1.618. The proportions of the golden rectangle are thought to reflect perfect symmetry. If we frame a gorgeous face inside of a golden rectangle, the dimensions of each will correspond perfectly. The face is beautiful because it is symmetrical.
   Amazingly, the golden ratio is found in many manifestations of beauty—not just in beautiful faces. The dimensions of the Great Pyramid of Giza in Egypt conform to the golden ratio. And the famous Greek Parthenon contains many golden rectangles. Moreover, the famous fifteenth-century Italian artist, Leonardo da Vinci, deliberately used the golden ratio in his paintings. Not surprisingly, the face of da Vinci’s Mona Lisa matches the golden rectangle.