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"Humor (from Latin "liquid," or "fluid"), in early Western physiological theory, one of the four fluids of the body that were thought to determine a person's temperament and features. In the ancient physiological theory still current in the European Middle Ages and later, the four cardinal humours were blood, phlegm, choler (yellow bile), and melancholy (black bile); the variant mixtures of these humours in different persons determined their "complexions," or "temperaments," their physical and mental qualities, and their dispositions. The ideal person had the ideally proportioned mixture of the four; a predominance of one produced a person who was sanguine (Latin sanguis, "blood"), phlegmatic, choleric, or melancholic. Each complexion had specific characteristics, and the words carried much weight that they have since lost: e.g., the choleric man was not only quick to anger but also yellow-faced, lean, hairy, proud, ambitious, revengeful, and shrewd. By extension, "humour" in the 16th century came to denote an unbalanced mental condition, a mood or unreasonable caprice, or a fixed folly or vice."
"According to their relative predominance in the individual, they were supposed to produce, respectively, temperaments designated sanguine (warm, pleasant), phlegmatic (slow-moving, apathetic), melancholic (depressed, sad), and choleric (quick to react, hot tempered). "
"Thus, a person with an excess of blood would be expected to have a sanguine temperament-that is, to be optimistic, enthusiastic, and excitable. Too much black bile (dark blood perhaps mixed with other secretions) was believed to produce a melancholic temperament. An oversupply of yellow bile (secreted by the liver) would result in anger, irritability, and a "jaundiced" view of life. An abundance of phlegm (secreted in the respiratory passages) was alleged to make people stolid, apathetic, and undemonstrative. "
"Blood, a hot, sweet, tempered, red humour, prepared in the meseraic veins, and made of the most temperate parts of the chylus (chyle) in the liver, whose office it is to nourish the whole body, to give it strength and colour, being dispersed through every part of it. And from it spirits are first begotten in the heart, which afterwards in the arteries are communicated to the other parts.
"Pituita, or phlegm is a cold and moist humour, begtotten of the colder parts of the chylus (or white juice coming out of the meat digested in the stomach) in the liver.His office is to nourish and moisten the members of the body.
"Choler is hot and dry, begotten of the hotter parts of the chylus, and gathered to the gall. It helps the natural heat and senses.
"Melancholy, cold and dry, thick, black and sour, begotten of the more feculent part of nourishment, and purged from the spleen, is a bridle to the other two humours, blood and choler, preserving them in the blood, and nourishing the bones."
"Choleric: "When the ego predominates, a choleric temperament results. Cholerics come across as people who must always have their own way. Their aggressiveness, everything concerned with their forcefulness of will, derives from their blood circulation. "
"Sanguine:

In the sanguine the nervous system dominates, and thus the astral body dominates (because the astral body expresses itself physically in the nervous system). "Sanguines surrender themselves in a certain sense to the constant and varied flow of images, sensations, and ideas, since in them the astral body and nervous system predominate. The nervous system's activity is restrained only by the circulation of the blood. That this is so becomes clear when we consider what happens when a person lacks blood or is anemic, in other words, when the blood's restraining influence is absent. Mental images fluctuate wildly, often leading to illusions and hallucinations.
"A touch of this is present in sanguines. Sanguines are incapable of lingering over an impression. They cannot fix their attention on a particular image nor sustain their interest in an impression. Instead, they rush from experience to experience, from percept to percept.
"Phlegmatic: This temperament derives from the etheric or life body. "The result is a sense of inner well being. The more human beings live in their etheric body, the more they are preoccupied with their own internal processes. They let external events run their course while their attention is directed inward.
"Melancholic:
"In the melancholic the physical body is master over the others. Melancholics feel they are not master over their body, that they cannot bend it to their will. The physical body, which is intended to be an instrument of the higher members, is itself in control, and frustrates the others. Melancholics experience this as pain, as a feeling of despondency. Pain continually wells up within them because the physical body resists the etheric body's inner sense of well-being, the astral body's liveliness, and the ego's purposeful striving."
"The Sanguine
" The sanguine temperament is an extroverted temperament. The child lacks the fiery inner purpose of the choleric and is activated more by what is going on around her. She has difficulty in concentrating on one thing for long and a new event easily distracts her. This restless changeability can be a bane for parents and teachers. A sanguine is often light-footed and rhythmical, but also light-headed and light-hearted. The interest she shows in everything makes her popular and a good social bridge-builder. Parties are great fun for her and she is seldom alone. Her face is expressive and mobile and her eyes easily sparkle. She is more likely to have curly hair than straight. It is hard for her to bear antipathy from a friend or an adult, for she is most herself when she feels loved. In extreme forms, the sanguine can appear superficial and may be unable to concentrate on a game or to amuse herself for long. It is good to encourage the sanguine to stick to a task.
"The Choleric
" Choleric is an extroverted temperament and the child likes to assert himself. He is usually ready to tackle a job which would make others pause. He is not shy, but looks at you with a steady gaze. He walks with a firm step. His will to be out in front marks him as a leader. He likes to have the main role in a play or to organise others. He can inspire the group to complete a difficult task. It is not unusual to see him red with anger and with eyes flashing. This temperament likes to win but seldom bears a grudge. Opposing the Will of such a child generally gets the parent nowhere. He needs to be appreciated and given things to do which challenge him and use up his excessive energy. He learns best from people who can do things well and whom he can admire. He doesn't easily learn from his mistakes. If guided well the choleric brings initiative and originality to his play. The temperament is fiery and this show in his paintings, where strong colours, especially red, and strong forms dominate.
"The Phlegmatic
" Phlegmatic is an introverted temperament. This child doesn't easily connect with what is going on around her, for her interest is not easily aroused. Eating may be a prime attraction and she may be rounded and clumsy. She is generally easy to bring up, so she may not get the attention she needs. She enjoys comfort and doting parents may over-indulge her. She needs to be stimulated to action or to take interest. She is generally placid and doesn't anger except when extremely frustrated. She is methodical, keeping her things in order unless she is so spoiled that, for the sake of comfort, she abandons her orderly ways. She can be counted on to do what she sets out to do, although speed is no object. She has a certain stubbornness, making her resistant to new ideas. She adores routine. Her love for food makes her gain weight and parents should impose a sensible diet. She needs to be encouraged to join in with other children and to try new activities. When she has found and interest in others, the phlegmatic is loyal and steadfast.
"The Melancholic
" This child experiences his physical body as somewhat of a burden. Instead of moving with a light skip (sanguine) or a firm step (choleric), he drags his feet. A minor physical injury causes excessive pain and while he likes others to know this, he doesn't want to be consoled. Cold water is to be avoided for he needs warmth. He usually avoids social life and prefers to play by himself. Remarks easily wound and are long remembered. When surrounded by different goings on, he chooses what interests him and is not diverted by other things. He gives himself up easily to his own-world fantasies, which tend to be rich. This pre-occupation with his own world appears very egocentric and further increases his isolation. But it is an isolation which he appreciates. This inner concentration gives the melancholic a special depth and understanding which parents can appreciate. He also asks profound questions about God or death. Such lonely souls need a great deal of love and understanding, but too much sympathy is unhelpful, for he is to some extent in love with his own suffering. Making him aware of others can often help to take him out of his self-centredness. While he never wants to be the heart and soul of the party, he appreciates a warm social environment. "
"A person with excess of the humour blood in him was called sanguine, and was pleasure-loving, amorous, kind, and jovially good-natures; the Franklin in Chaucer's The Canterbury Tales is such a figure. Someone with an excess of phlegm in them was described as phlegmatic and was dull, cowardly, unresponsive, dour, and unexciting. An excess of yellow bile gave rise to a choleric person: vengeful, obstinate, impatient, intolerant, angry, and quick to lose his temper. An excess of black bile produced a person who was melancholic: moody, brooding, sharp-tongued, liable to sudden changes of mood, and often lost in thought and contemplation."