The peculiar physical and mental character of an individual, in olden times erroneously supposed to be due to individual variation in the relations and proportions of the constituent parts of the body, especially of the fluids, as the bile, blood, lymph, etc. Hence the phrases, bilious or choleric temperament, sanguine temperament, etc., implying a predominance of one of these fluids and a corresponding influence on the temperament.
This was a system that Hippocrates used for relating a number of common conditions found in people. He described four temperaments, and each type was characterized by a similar psychology, metabolism, and pattern of illnesses. The four types are given in the following table, taken from Classical Astrology for Modern Living: Air Libra, Aquarius, Gemini Sanguine Wet, becoming Hot Fire Aries, Leo, Sagittarius Choleric Hot, becoming Dry Earth Capricorn, Taurus, Virgo Melancholic Dry, becoming Cold Water Cancer, Scorpio, Pisces Phlegmatic Cold, becoming Wet Sanguine types are the jolly glad-handers; choleric type fly off the handle; melancholics are morose and brooding, and phlegmatic are lethargic. The temperaments system was recognized and used by all Galenic physicians, whether they used astrology or not in their practice. The astrologically-inclined would add the ability to calculate the temperament from the nativity, and the ability to predict challenges to the temperament based on the hard aspects of the Moon the to decumbiture chart.