Four temperaments
![18th century depiction of the four temperaments[1]Phlegmatic and choleric (above)Sanguine and melancholic (below)](/uploads/202502/02/Lavater17924421.jpg)


Four temperaments is a proto-psychological theory that suggests that there are four fundamental personality types, sanguine (optimistic and social), choleric (short-tempered or irritable), melancholic (analytical and quiet), and phlegmatic (relaxed and peaceful). Most formulations include the possibility of mixtures of the types.