The Vitruvian Man.

 Leonardo's famous sketch was made as a study of the male human proportions. It was based on text written by the ancient Roman architect Vitruvius.

 This iconic image typifies the mix of science and art present in Leonardo's vision of the world. It is a prime example of a mind attempting to marry together the perfect proportions of the male form and link them to nature. He believed that the workings of the body are linked to the structure of the universe itself and this work is a fine example of Leonardo's constantly inquiring mind.

"The Vitruvian Man"
1485 Accademia, Venice.

Leonardo da Vinci.

The image and the Euro (w)

The multiple viewpoints seen in the drawing serve to illustrate that there are no universal set of proportions for the human body.

 Vitruvius states that the centre of the body is the navel, but Leonardo's sketch shows that this depends on the position of the arms and legs, and when the figure is in the standing position, the centre of gravity is actually lower than the navel.

 This worldwide icon is used in various forms in the modern world and is closely associated with the medical profession. It has been used a symbol for rock bands, NASA, and the Euro. 

Personal opinion:-

 Many theories abound about this work, secret meanings and a whole industry based on The Da Vinci Code (a work of fiction but a great read) and astrological and mystical interpretations of the sketch.

 I confess I don't know if any of these are factual but I prefer to view the work for what it is, a geometrical study that has stood the test of time. The drawing fascinates us and is the product of a Renaissance artist, scientist, mathematician, inventor, anatomist and engineer.

 Enjoy it, Leonardo, what a guy!