Avicenna On the Four Temperaments from the Canon of Medicine Volume 1

The Temperaments: Cold and Dry, Cold and Wet Hot and Dry, Hot and Wet Ibn Sina divides temperament into that which is harmonious and that which is non-uniform. Wikipedia. Ibn Sina says: In addition to the signs of the normal temperament already given, there are: Mental faculties including: vigor of imagination, intellectual power, and memory. . . . In brief, there is non-uniformity of temperament among the members; or, perchance, the principal members depart from equability and come to be of contrary temperament, one deviating towards one, another to its contrary. If the components of the body are out of proportion, it is unfortunate both for talent and reasoning power. Canon of Medicine.