According to the Greek physician Claudius Galen (129-199 CE), a person’s health was determined by the balance of the four bodily fluids, known as humours. If the ratio of these humours changed in a person’s body, they became sick. Healing was only possible by restoring the correct balance. It is also very important for a healthy city to be in balance with the environment. The scale here symbolises the age-old quest for balance.