The melancholic is winter; it is earth; it is mineral. Where sanguine is light and airy, melancholic is heavy, deep, cooler, more reserved. The melancholic temperament does not jump into action, it observes and considers; it contemplates. They rarely speak, but when they do their words reveal a profound consciousness (in the mature melancholic). This temperament will not create the great leader of action, or the social balm, or even the steady-as-she-goes reliable worker. This is the temperament of the wizard or sage, those who often retreat from the world to work on something in private. If this temperament does make any friends, it is only with one or two people and those friendships are deep and all-important. Worst case scenario, these friendships are entanglements of codependent behaviors and emotions.
When the melancholic temperament remains immature, it has the tendency to fall into morose depression. It feels, deeply, the difficulties of life on earth. It notes the hardships and the pain. It sees every imperfection and mourns it. While immature, the melancholic falls into a pit of self-pity and inactivity. "Why do anything when everything is so difficult and imperfect and we are just going to die anyway?" Unfortunately, this is how the melancholic temperament is epitomized. It is too easy to stereotype the immature version.
The mature version is so important to understand and achieve however. Rudolf Steiner said that it is the most important temperament for the parent and for the teacher to cultivate and mature, because when it is mature, it turns from self-pity to compassion for others. Yes, it understands the difficulties and pains, and so it can relate to others who are struggling--and we ask children/students to struggle a lot. Or, we should be doing so. Learning is often a struggle. If we remain in our comfort zones, we learn very little. So, learning and growing is often difficult. It can bring one to the point of giving up. The mature melancholic parent/teacher can understand this and help that individual work through it with compassion. When mature and balanced with other temperaments, the melancholic is not the hermit who retreats from society, rarely willing to share its wisdom, it is instead the wise counselor, it is the healer. It brings its gifts for deep considerations and shares them with others who often need a new perspective and/or understanding.
It is easy to see how the sanguine needs the melancholic for balance and how the melancholic needs the sanguine. Without each other, each becomes a parody of extreme stereotypical actions, and the gifts of each would be lost or minimized.