The human body was thought to be a miniature representation of the universe as a whole. Various parts of the body were linked to the planets and the signs of the zodiac. Things that happened in the universe, which was known as the "macrocosm," were supposed to
happen on a much smaller scale within the human body (the "microcosm").
The body was also thought to contain four "humours," or fluids -- black bile, phlegm, blood, and choler. A person's temperament depended on the way the humours were mixed. In JULIUS CAESAR, Mark Antony describes Brutus as a man in whom all these humours are mixed perfectly. But most people were thought to have one humour that was more dominant than the others. Hamlet is a famous example of a character with too much "black bile," causing a melancholic, depressive temperament. Illnesses and mental disorders were blamed on an imbalance of the humours.