ëA magnificent temple cannot be constructed properly, unless it is built in an orderly manner with regard to symmetry and proportion of its parts, as is the case with a well-built man. For the human body is designed by nature, put together and created so that the head from the chin to the hairline measures one tenth of the entire body. Likewise the flat or extended hand from the wrist to the tip of the middle finger is equal to the distance from the chin to the part of the hair, i.e. one eighth part. Likewise from the bottom of the neck and the high point of the chest to the hairline, one sixth; and to the top of the head, one quarter. But to the level of the mouth, one third; from the tip of the chin to the nose, from the tip of the nose to the midpoint of the eyebrows, and thence to the root of the hair, each one third. The length of the foot is one sixth of the body length, the forearm one quarter, the chest one quarter. In this manner all other limbs have their proportional measurements, which were observed by ancient painters and sculptors.í

A mathematican adds: 'Michelangelo made countless drawings and measurements of the human body (living and dead, as well as Greek and Roman statues) in order to understand its shape, proportions and variations. Of course, human proportions vary with the individual, but in classical art, the body of the ideal figure is 8 head-lengths from head to toe. In real life the adult human body is 7 to 8 head-lengths. Dürer favoured 7.5 head-lengths in his pictures, Rembrandt used 7, while Giacometti at times used 12. The figure of David uses 7 head-lengths....'

More Renaissance mathematics...