According to Galen, which of the following had an important role in temperament and character of a person?

The role of the four humors

Galen elaborated on the role of the four humours in personal character and temperament. According to him, the material world was made up of four elements, viz. earth, air, fire, and water which combined to form four essential body fluids, viz. blood, black bile, yellow bile, and phlegm. Each of these fluids was seen to be responsible for a different temperament. Imbalances among the humours were believed to cause various disorders. This is similar to the Indian notion of the three doshas of vata, pitta and kapha which were mentioned in the Atharva Veda and Ayurvedic texts.